Satoru gives a surprised whimper of desire as Suguru’s thumb pushes into her mouth like that. Even though she didn’t anticipate it, the obviously erotic gesture helps to ground her, making her more certain of what she wants. They’re doing this. Satoru does want her. Has wanted her for far longer than she realized, and now that there’s an actual possibility of it, Satoru isn’t going to let go. Suguru is hers.

She rubs her tongue against Suguru’s thumb, heated and inviting, sucking on her with a little moan.

The way Suguru answers her question certainly isn’t how Satoru meant it, and she doesn’t believe that Suguru does really know what she’s getting herself into. (Largely because it’s Satoru dragging her into it, renewing her efforts every time Suguru tries to squirm free.)

Suguru’s warning just draws a lifted brow, however, because she needs more context. Sharing what? Sharing the bus? Her bed? Her time, her things? Sharing Satoru herself? (Doesn’t that last one imply a claim? If she will not share Satoru, it means that Satoru is hers.)