Nostr sounds like no star, which in Japanese is either x's star (star belonging to x), or star that has the characteristics of x. In this case, it's "star that has the characteristic of being nurunuru (slimey)" Not sure where the slime thing came from though.

Nuru also means lukewarm, so it could just be a play on words. a casual project (lukewarm)/slimey

While linguistically true, this seems not to be the intentions of the name. Fake news!