It was a fine and funny episode. Skuld falling for Keiichi was somewhat natural. He's the only adult male she's regularly in contact, and he's a decent and friendly fellow. I guess this episode made Skuld realise better why Belldandy is with him. It has been a while since I watched the actual series, but isn't Skuld's only real reason to hinder the relationship the fact she fears she will lose her oneesan?

Keiichi was surprisingly OK with the idea when the photographer ordered the kissing scene. Is it so that he can't kiss Belldandy, because he really loves her, and that makes him nervous? He could pretend to kiss Skuld because it wouldn't have meant anything deeper. So, it's not really the idea of kissing, but what's behind it.