Interesting premise, if slightly confusing. Not sure what a "Fae realm" is. I'm only a couple chapters in, but there were a few things which irked me.

• It feels a bit too American. For example, Harry would likely say 'torch', not 'flashilght'.
• There were a couple muggle terms (like holster and radar) which seemed out of place. In particular, radar would have been a fairly recent (and secret) invention in Tom's timeline, so it seems odd that he would know about it and have an equivalent spell for it.
• The historical characters sometimes speak too candidly for their timeframe. For example, "maybe we swing around to the dorms, make out in your old bed" doesn't seem like language someone from 1899 would use.

In any case, thanks for sharing! I might read the rest of it at some point.