User blog comment:MrCents 04/Is Ains / Momonga can become a human?/@comment-27008999-20151023212022

If I was Ainz I wouldn't change race until I had made sure there are no longer any big threats that might kill me. Changing race takes exp. away and probably all racial classes you had before using the racial item and all job classes related to that race or something that cannot be used on another race.

If Ainz became an angel for example, he would lose not only his racial levels and exp., but also his necromancy skills. Angels don't dwell in death and resurrection, and it's also closer to an evil alignment, something an angel would never come close to. Overlord is inspired by D&D after all, so that counts as well (Don't try to bullshit me, you know it makes sense).