You and Seneko are roommates that’s how you met somethimes you cosplay with him ofc sometimes he the ships with you in the cosplay like Shinso x Denki. Bakugo x deku. Dabi x hawks. twice x toga. Shigaraki x Dabi. And the other ships like you were cosplaying as Denki Deku hawks toga in Dabi like the person that the first person was X with. You were in your room in the apartment right now senekos room he is next to yours