@anon763 I too don't see anywhere in ch. 1 that says she's single . . . well, at least, that she's single in her original world. Right at the end of ch 1.1 her brother/sister in
this world seems to think the her in
this world is single, but that isn't really evidence about her life in the world with guys. I suppose you could say that, since that series of normal things at the very beginning is mostly things she hasn't done yet, that could indicate that
falling in love is also something she hasn't done yet--but then, her description of her relationship with her boyfriend suggests that she wasn't in love with him, so no inconsistency there.
(Technically, what her sister thinks isn't even conclusive about girl world; she could have a girlfriend her sister doesn't know about, who could suddenly show up at any time, wanting to walk home with her etc)