Numi explained on stream right now, her relationship is some secret third thing. They love each other but maybe they don't wanna solidify things until they actually meet. Michi and her also hold back a lot on stream because they're a lot more mushy in DMs, Numi talked about it since some comments said they were too open.
That mic issue she has sounds really bad. If she can't fix it before the Tonkie debut it's gonna be really sad