Hiroki Prince's Links
Hiroki is more than in love with Ace - Ace is their entire WORLD. Hiroki depends on Ace to drive them around and help them with income, as well as helping them with day-to-day things (as Hiroki is nearly blind).
Its sometimes hard to tell how Ace feels about Hiroki, as he is really quiet and doesn't seem to connect to people very well. However when he is threatened with Hiroki leaving he becomes very distraught and upset because he adores Hiroki and doesn't want to ever lose them.