Season 2 begins with Aoi having a crazy nightmare about her and Hinata climbing Mt. Fuji. Aoi is angry with her for leaving her behind in the dream, until Hinata invites her to camp with her, Kaede and Kokona in the mountains. But when Aoi's mother hears about their plans, she forbids her daughter from going. They wind up camping out at Hinata's house, where the seeds of future adventures in climbing are planted.

The Girls plan a surprise for Aoi, planning a mountain climb to surprise her with a view of Mt. Fuji when they reach the top. But keeping the secret of the climb proves to be harder than they thought.

Aoi gets much needed encouragement from Kaede as the climb up Mt. Mitsutouge grows more and more difficult. But even as one surprise is spoiled, another surprise awaits at the top.

The girls reach the summit of Mt. Mitsutouge, and the view of Mt. Fuji sends Aoi into an exuberant reverie. But the descent down the mountain presents as many challenges as the ascent, and Aoi's legs begin to give out. But relief awaits at the bottom of the Mountain in the form of a Hot Springs. Will Aoi be too embarrassed to bathe in front of everyone?

Aoi and Hinata get into an argument. It starts with Hinata doing something embarrassing to Aoi when they were in Gradeschool, an incident that gets repeated again. But soon the argument grows in anger from Aoi when Hinata ruins something precious.

After listening to Hinata's father tell of his ascent up Mt. Fuji as a teenager, Aoi decides she wants to attempt the climb. Hinata and Aoi make plans to make the climb at night so they can watch the sunrise, but Aoi's mom refuses to allow her to go.

While Visiting Azumo Gorge, Hinata convinces Aoi that swimming would be good strength training for the climp up Mt. Fugi. But when they invite Kaede and Kokona to join them, Hinata tells them to wear their "sexy" swimsuits. Not knowing what makes a swimsuit "sexy", Aoi sets out to find one for the swim.

The plans are set, the reservations are made, and it's the day before the ascent up Mt. Fuji. But Aoi is beginning to have doubts about whether she can make it all the way. But when she finally decides to tell her friends about her worries, she is surprised by their reaction.

After spending some time acclimating at the Subashiri 5th station of Mt. Fuji, the girls take the Yoshida trail and head to the summit. As they ascend, the increasingly thinner air begins to make the climb more and more difficult.

As the girls climb higher up Mt. Fuji, and they are surprised when they all agree that the climb is much more difficult than they expected. Aoi develops a case of Altitude Sickness, and it's agreed that Hinata and Kokona should go on ahead while Kaede and Aoi stay behind and rest. The girl agree to meet at the summit at sunrise, but...

Having succumbed to Altitude Sickness, Aoi winds up staying at the 8th station as Hinata and Kokona make it to the Summit. After talking to Kaede on the phone, the two of them agree to walk the basin of the volcano. While they are there, they both write letters to Aoi. Kaede and Aoi begin the descent while Hinata and Kokona reach Kengamine peak, 3776 meters and the highest point of Mt. Fuji.

After her failed attempt to climb Mt. Fuji, Aoi is depressed and hasn't spoken to Hinata at all. Some time after Summer break begins Aoi receives the letters that Hinata and Kokona sent from Mt. Fuji, and after reading them Aoi decides to go for a walk by herself. Soon she finds herself at the foot of Mt. Tenran; the first Mountain the two of them climbed when they met again in high school. When she reaches the top she runs into Hinata, who drags Aoi on to climb Mt. Tounosu (which is next to Tenran) that very afternoon. At the top, Aoi admits she's been frustrated and depressed...

After being invited to go firefly watching, Aoi and Hinata recall that they once went firefly watching when they were younger. When they ended up getting lost, they were led back to their parents by an alleged firefly, though they both have different ideas about what kind of firefly it was.

With Aoi's mother still cautious about her climbing up mountains again, Hinata and her father suggest that she invite her to climb Mount Kirigamine with them. Whilst climbing the mountain, Aoi is reminded of the mountain she climbed with Hinata when they were younger, though neither can remember which mountain it was. Hinata's father later reveals that mountain was Mount Tanigawa, leaving the girls excited to try and climb it once more.

Upon finding an old raincoat in her closet, Kaede recalls her middle school friend, Yuuka, who was often concerned about her climbing mountains. When Yuuka got upset with her after she ended up spraining her leg, Kaede came to realise she had never taken Yuuka's advice to heart and apologised, after which they bought a raincoat together. Feeling nostalgic, Kaede rings up Yuuka and the two go out shopping together.

Aoi is anxious about climbing Mount Tanigawa as it involves riding a cable car, which isn't good for her fear of heights. Later, Kaede invites the girls to her house, where she explains she too was scared whilst riding a cable car, but found it less scary on her second go. As Aoi is encouraged by Kaede's words and decides to take on Tanigawa, Kaede gives her her old raincoat that she bought with Yuuka.

Wanting to help Aoi get over her fear of heights, Hinata takes everyone to Shinrin Park. After participating in various activities, Hinata helps Aoi to cross a suspension bridge before managing to get her to try some bouncy mountains.

Running low on funds for her mountaineering, Aoi applies for a part-time job at a cake shop. There, she meets college sophomore Hikari Onozuka, who shows her the ropes. After a hard day of work, Aoi feels her horizon has expanded a little.

Having made much progress in her preparations for the Mt. Tanigawa trip, it soon dawns on Aoi that she hasn't touched her summer homework. With Hinata on vacation, Aoi asks Kaede to help her out, only to find she hasn't finished any of her homework either. Kaede instead calls in Yuuka to help tutor them over the next week, allowing them to get it done in time.

On the day before the Tanigawa climb, Kokona, whose birthday is on the same day, gets some new shoes as an early present from her mother and decides to go on a walk to Akebano Children's Forest Park to try them out. After returning home, Kokona celebrates her birthday with her mother, who ran a little late home from work. Meanwhile, Aoi, who spent the day making a pound cake, wonders about what will happen after her dream is fulfilled.

The day of the Mount Tanigawa climb finally arrives, with Hinata also pondering what will happen after she and Aoi fulfil their dream. After a series of staircases and some obligatory forms, the girls arrive at Tanigawa, where Aoi must face the cable car first hand. Despite Aoi still being afraid, the other girls help her get through it before Hinata helps her ride a ski lift.

As the girls officially start climbing up the mountain, they encounter a quiet young photographer named Honoka, who had previously helped them by the cable car. Interested in her, Aoi decides to follow Honoka as she goes about her photography. After encountering some rainfall, the girls arrive at the mountain hut, where Aoi and Hinata look back on memories of their previous time there, worrying what happens after their promise is fulfilled.

The girls have Honoka join them for dinner, where they celebrate Kokona's birthday together. Later that night, Honoka gives some advice to Aoi concerning her promise, and the two exchange contact info with her. The next morning, as the girls continue their ascent, Aoi and Hinata look back on their recent adventures as they finally watch the sunrise together, realising that their promise will continue forever as they keep making memories together.

On the day the Aoi invites Honoka to join her and the others for a fireworks festival, she and Hinata get into another argument with each other. As Aoi takes Honoka on a tour of Hanno, she can't stop thinking about Hinata and decides to try to make up with her, while Hinata hear how Aoi feels about her from Hikari and decides she should apologize too. Both have trouble finding an opportunity to apologize to each other during the festival, but soon find they don't really need to, quickly forgetting why they even fought in the first place.