Fun game, although it's a challenge to run it having never played Bloodborne. I ran a one-shot game through a version of Heliwyr heavily influenced by H. P. Lovecraft's Shadow Over Innsmouth, lots of watery critters and cthulhean "sirens", and that worked really well. The game could easily stretch out to something quite long, or play through very quickly, depending on player choices and how much RP is happening, so be prepared for that.