Maybe this is a headcannon, but after reading chapter 13, and all the hints troughtout the manga, I think is safe to assume Suzuki-kun is his own father reincarnated, not only is he like an exact clone of him, but he also shares personality traits and attitudes with him, and more than anything else the flashbacks, those flashbacks are more like the ones of a past life than his father spirit giving him his memories with his mom