Ah yes the classic trope of a protagonist well into his 20s getting it on with a girl that’s like 13.
Either way it was very blasé and typical, if I search the isekai tag I reckon I could find one exactly the same, what’s more using historical figures and not even characterising them somewhat accurately or in an interesting way, you can’t expect to put someone like Jeanne D’Arc, a woman from the 15th century in and act as if there’s a connection between the knight loli and her. Same with Hijikata Toshizō, there doesn’t seem to be much depth beyond the typical tropes that they display. I also kind of find it funny how they tried to make it seem Hijikata Toshizō’s death was this epic scene being killed by 1000(?) bullets when he just got shot in the back.