Ever since Tsukkishima Kei and Kuroo Tetsuro started Dating, Yamaguchi Tadashi has been left on the sidelines, third wheeling and lonely. It had been like that until Yamaguchi couldn't take it anymore and wanted a lover. But After meeting Terushima Yuji his life started to change. But then Tsukkishima had learned about their relationship and realized he was afraid that his best friend might be taken away by a flirty asshole.