Isso, Koi Dattara Yokatta no ni

Overview

Nina had always admired Mao, her senpai from high school. Mao was a diehard rock fan and talented musician who was as gentle as she was strong-willed. When it came time for Nina to pick universities, of course she wanted to follow Mao. But when the two finally reunite, Mao is almost a completely different person...and she's quit music! While Nina is happy to learn about how her precious senpai has grown, there's one problem: the guy who causes Mao to look so soft and tender. But this nice-looking-guy isn't treating Mao the way Nina believes she deserves. Her solution? Show Mao-senpai just how she deserves to be treated by taking her out! (Source: Seven Seas Entertainment)

Source: AniList