Even as a straight guy I see the appeal. He's like a child, and he's definitely cute, but those are factors for initial attraction and nothing else.
Even though I can't say I'm anything close to an expert on gay relationships I do know about basic human dynamics, and I'm pretty sure those initially attractive traits aren't the basis for a healthy relationship.
I'm pretty sure Yanda is not a paedophile, but still I don't know if I'd let him spend too much time around the kids.
He's basically on Ena and Miura's level of maturity.