"Falls Hood Girls Academy"
Well played...
Given that his twin sister is pretty stacked herself and Kaya is pretty touchy-feely with her, I think she'd have already noticed just by being close to him even if the entire thing wasn't one big scheme of theirs. There's also his voice which should be difficult to fake at this age and which sometimes feels unaccounted for in crossdressing manga.
Loving how she's actually not some dense ditz waiting to get confessed to, but secretly and proactively aiming for him, the boy she loves. Mutual attraction is always a better romance than someone one-sidedly chasing after another. I'd prefer proper communication too, but this is better than one or both actually being dense so I'll take it...
Has potential for serialization, and let's not forget
his twin sister is ALSO crossdressing as a boy at her school since they swapped places. That's a ripe plot point just asking to be explored.
Trying my best to decide what the ハメ in the title is...
The fact that Hame (
ハメ) is written in katakana makes it very sus, because Hame (はめ) can also mean "to entrap" / "to deceive" which seems like it should be the more apt meaning instead of, y'know...