Anna always told him that what he did with Hao was fucking, and what he did with her was making love.
He believed her (because she was Anna, and he loved her) but he didn't see the difference. He didn't see what he did with Hao as being a bad thing like Anna did. It was just simply that. What he did with Hao.
It was… the same…?
Making love/Sex/Fucking/…???
Yoh preferred not to think about it, and simply enjoy what happened around… and in him.
Yoh tells himself they make love, and Hao says they have sex, but the truth is that all they ever do is fuck, fuck, fuck.
Fuck their family and fuck their lives and especially fuck each other.