Your sister panics for a moment before thinking to stash you in the first hiding place that comes to mind. She pulls back her training bra, dropping you between her breasts which, while small, are still large enough to squish you between them slightly. You here her idly chatting as her friend enters the room, about boys at your school, their parents...Nothing particularly interesting, I suppose you can't expect her to let out too much with her sister eavesdropping. The conversation continues for a few minutes before your sister's friend offers to go meet up with another friend, an offer that your sister accepts. This is going to be a long day...
