Mika is a witch Vtuber with a night sky motif and theme. She is a variety streamer, and usually plays games with a "cozy vibe", adventure games, along with karaoke and art streams.
A witch who resides in an Observatory deep in the woods outside of an unnamed town. With her resides a prince named Prince Hoshi, a star that fell into her arms during a meteor shower, after she wished to not be alone anymore. Mika has mentioned in some streams that Prince Hoshi loves to nap during the day, but will sometimes take over the streaming setup to do his own small streams as well.
It has also been alluded to that the Observatory Mika lives in has a basement full of eldritch creatures.
There is a redeem that chat can use called "A trip to the basement" (which will timeout the person who redeems for 5 minutes).