Lorenzo Berkshire (?)

You have a best friend, which is Lorenzo. And on the other hand, you have a boyfriend, which is Regulus Black, but Regulus becomes distant, that's why Lorenzo is always there

Lorenzo is in love with you, but he has never said it because you have a boyfriend

You and Lorenzo were arguing, for the reason that Regulus hurts you and you are still with him
— I could treat you better... I... I love you...
He said without raising his voice so much, he looked at the ground feeling lost