So who is this "Reiny" person that Rin is collabing with....
oh
Ah, it's @HuskT's oshi.
Interesting that she's obviously open with her mother about her vtubing activities when she's doing this kind of stuff on stream. It looks like she does a lot of more typical gaming content too so she doesn't seem like a shameless Twitch thot-tier streamer, but it's still there to a degree.