I feel like this is directed at the viewer. As in, she's saying "No special art or show for you today, I'm busy with my girlfriend." Having it be NTR would be a bit odd, since the artist does a lot with these two and they feel pretty established in their world.
There's literally no source provided here, and if there was truly something problematic about the two the vtuber drama community would already be in arms about it and yet there is absolutely nothing, so I'd advise you guys to take that accusation with a barrel of salt.