Also mentioning it doesn't fit to Rainbow's character.
True.
I lol'd, so he's like a weeaboo with a waifu and the money to pay for commissions. I honestly don't see the crime yet.
It is actually, I'm looking through his gallery and they're not like explicitly loveual, they're extremely tame.
I fail to see the evil in this.

Still, everyone (myself included) hates him for it. I don't really even know why, but something about that guy REALLY pisses me off.
EDIT: Maybe it's that "big brother" mentality, where we've all become over protective of a "little sister" figure (in this case RD). Perhaps it's a "jealous boyfriend" mentality. Either way, a lot of bronies feel that Skywind has crossed the line with his shipping of himself and RD.