Junjou Decamelon - 1

The main character is a young schoolboy who once night watched the stars in his telescope in the park. Suddenly, a girl of impressive growth appears there, who was almost naked. After this perverted meeting, the life of the protagonist changes abruptly when a new student named Momot is translated into his class. He is shocked, realizing that this is the tallest girl he saw in the park. Momota admits to the guy that that meeting in the park was a desperate attempt for her to raise her self -esteem. She also told him that her former classmates constantly treated her disapprovingly due to her great growth. Now that he learns the whole truth, they begin to become closer to each other with both emotionally and physically.
in the second part of the series, their first date takes place in the planetarium. While they were together with the group, Momota could not resist the desire to release her perverted essence in the dark. When a walk comes to an end, Kaede realizes that he enjoys only when he feels the gaze of others.