Time for sum ship headcanons
Ouma likes to steal shuichis hat and pretend that hes the detective himself mainly just to tease saihara (which it works)
Ouma is very needy in the relationship so he tends to beg for cuddles whenever saihara is around.
Shuichi has grown to kokichis lies. Hes able to tell when hes lying and uses it to blackmail him afterwards.
Kokichi loves to play pranks on shuichi but the plans always backfires since shuichi know when hes pranking him.
Ever since they started dating kokichi has gotten to be a lot nicer to the cast because shuichi has been taming kokichi a bit. (He still is a little trickster and that will never change:3)
Kokichi LOVES to surprise saihara with kisses. Hell just pop out of no where and give him a peck on the cheek leaving the boy all flustered which pleasures ouma.
Shuichi forces ouma to watch mystery movies with him and to his surprise kokichi is interested in it.
Kokichi gets jealous reeeaal easily. He hates it when kaito, k1-b0, or any of the girls talk to shuichi.
"Leave my shu shu alone!!!"
And kokichis many nicknames to embarrass shuichi with. "Shu-shu" "shumai" and your other basic couple nicknames like "sweetheart" and stuff
