I dunno — in S2E10, when Kasumi volunteers Shizuku's house for the "training camp" and hangs out with Ophelia for late night plotting, it comes across as if she's over there all the time. I mean, it's no being tackled onto a sleep sofa, sure, but...
FWIW this pic is oriented incorrectly; should be rotated 90 degrees counterclockwise. They're actually laying on a bed, not pinned to a wall (can tell by the direction of the sweat drips.)