Kirishima and Kuroda would be an interesting pairing, as you imply. I could see Kuroda having a boyish side and Kishima being a bit of a nag, but who knows. I don't know id Kirishimia reads for fun. I don;t know what he does for fun (though sex is certainly a good guess--and we have some BDSM hints).
I would kind of like to see Kirishima with someone who takes over and makes him loose control. Maybe Kuroda is mischievous enough to do this. I don't know.
Kirishima has an older female friend they have an" understanding" for years. He lives a quiet life. His neighbors would never know what he really does for a living. His abode is modest, even though he is rich. Rides his motorcycle to and from work and knits to relax. He likes to live alone. his present work load would be to hard on a live in lover. his first love is his work after all and who could understand that? Yet he is happy.
Question what do you think Kirishima Kei is like off the job.? what does he do to unwind ? does he share books and leather with 'cough' another glasses wearing fanatic, or is a sumo body in an apron waiting at home for him?