I think this is gonna turn like those angsty stories. Its kinda obvi sense Happy(Seungmin) is going in and out asking personal questions about Happy's(Mc) personal lif without his knowledge. I hoppe they communicate and find out who drugged our innocent and adorable Mc. But for me personally I kinda think the culprit behind it is one of happy's(Mc) ex-group mate from when he was still an idol. And the order was from the company higher up.