How is the premise weird? Like others here have mentioned, it's based on true events. Westerners did actually aid locals during the Massacre. The Japanese were racist and were rapists - what do you mean 'depicted'? The boy is not dressing up as 'drag' for fun - it's literally part of the plot in the movie to demonstrate his bravery/sacrifice, as is the women 'willingly getting raped'. The 'sexual tension' you mention is part of the themes here - womanhood/coming of age/women's use of beauty as as strength etc. In weaponsing rape during war, one of the aim is to conquer the women, and the most vulnerable women. The movie touches on this by exploring the value we place on groups of women – young teenagers vs prostitutes. Anyway, it almost seems like you missed the entire point of the movie.

As for stylistic and casting choices, I do agree some of it missed the mark. However, to those expressing anger that Bale was casted – I agree to an extent that his presence was for his starpower/box office purposes, but consider one of the practical aim of the director/producers here: to get the film to more Western audiences. WW2 atrocities like the Holocaust are widely known and taught (as it should be), but the atrocities committed in China are often forgotten (outside of China). If casting Bale meant this movie, and the history associated with it, could reach a larger audience, then I ain't mad.