I agree, since his “beloved” had also slept with both men AND women, but shuraka was fine with it. And if shuraka doesn’t love or care about the concubine— he shouldn’t even care who he sleeps with….
It's not that he dislike the pink haired man sleeping with others, he doesn't care about that. He dislikes him telling Shuraka that he loves Shuraka because Shuraka doesn't want anyone loving him other than Tei and the reason for him telling the pink haired man that "if you love me why will lay another man" is an argument to discredit the justification the pink haired man said of loving him.
First- tei slept with people BEFORE he got married to shuraka. 2. Shuraka didn't gaf about pink hair till he started calling him beloved and saying that he loved him shuraka snapped because only his MAN TEI CAN call him beloved and also HE was pointing out how much a hypocrite/ manipulative pinky is was Being.
Why Shuraka didn't like the pink haired concubine sleeping with others? I don't really understand it.