It's a Promise

Yūto is invited to come with the Nogizakas to a ski resort in the mountains. He thinks it is just for them but he quickly finds out the entire class is coming on this trip. While the group enjoys all the hot spring resort has to offer, Shiina sees the trip as an opportunity to express her feelings to Yūto—but in an attempt to hug him, she ends up groping…

Synopsis excerpt via Kitsu.