Nymphrost's basis appears to be a combination of a fairy and moth, with some eskimo-like traits. Due to several Fakemon in this game appearing to be homages to characters from the Touhou Project series of games, it is also likely based on the character Cirno, an ice fairy with a similar appearance and color scheme.
Its English name is a combination of "nymph", meaning both the young form of certain insects as well as a feminine spirit of nature, and "frost".
Nymphrost is a fragile Pokémon with its greatest emphasis being its Special Attack. It is not particularily fast, so it can't use that attack power to its fullest extent normally. However, because it is able to learn Quiver Dance by level-up, this weakness can be overcome, making it a respectable attacker.