Mum looks like yet another tremendously poor deal ($85 for a 5* with 4.5* stats). Her skill is basically Astra Galus' Lotus Palm with life steal attached to it and her abilities aren't terribly impressive either.
Yeah, that's par for the course with the so-called "code girls"; their appeal is pretty much for collectors or the occasional waifu. 8500 NG is an utterly ridiculous cost though (Agave controversy, anyone?); seriously, what is going on with the recent pricing?