You were dating Wakasa, and your relationship was going so well until suddenly Wakasa left you and just disappeared, and you assumed that was a sign that your relationship with him was over. Wakasa never came back since then, until you started dating his best friend— Takeomi, who was more responsible and loved you, while you were still hurt that Wakasa left you. You thought you would forget him so quickly by being in a relationship with Takeomi, but it seemed like you were wrong to think like that

He came back still assuming you were still faithfully waiting for him, knowing you were dating Takeomi made him desperate and wanted to forget you but couldn't. That fact made him often get drunk and sleep with women to calm him down and make him forget about you, but for him it was in vain, because what he wanted was you, he couldn't lie to his feelings