Nymph♀

Nymph is an "Electronic Warfare Angeloid, Type Beta". She is introduced when she finds Ikaros on an errand and attacks her, then later mysteriously appears in Tomoki's living room where she casually snacks on chips. She has a condescending attitude towards humans, whom she refers to as "bugs", and she calls Angeloids by their types rather than their names. For example, she calls Ikaros "Alpha". Despite the attitude, she starts enjoying everyday life and her favorite hobby is eating snacks and watching soap operas. After spending more time with Tomoki and his friends, she begins to like humans, and soon develops feelings for Tomoki, albeit in an aloof fashion.

Nymph is named after and based on the nature spirits of the Greek mythology.

Nymph's original mission was to retrieve Ikaros and return her to Synapse. (spoiler hidden)

[Edited from Wikipedia.]