I Think of You Often - St. Acton, #1

For Evangeline "Evan" Miles, Honeycutt Academy is more than just a prestigious school of magic. It's home. Before graduating, it was the first place they'd ever felt comfortable enough to be themself. Now, as a school librarian, it's also where Evan might have finally found the promise of love - with Mimi, the bright and bubbly potions professor. But when Evan meets Hester, the half-sister they never knew they had, everything suddenly changes.
Hester is being stalked by their murderous, vampiric father - an experience Evan remembers only too well. United, the two siblings agree that their days of running and hiding from their father are over - and it's time to finally end his wretched existence. But to do so, they must turn to Svenja - a witch, a wolf-shifter, and the only creature they know powerful enough to take down their monstrous father.
However, the paranormal private investigator is also Evan's former lover - and as the hunt for their father draws them closer together, the flames of their romance begin to rekindle. Evan feels forced to choose between their chemistry with Svenja, and their commitment to Mimi - and that distracts them from a dangerous truth: That as Evan and Hester prepare to confront their centuries-old father, they've forgotten he's also had decades to prepare for them. I Think of You Often is the first installment of the St.
Acton series by Sienna Eggler - a small town sapphic PNR by an author praised for writing "engaging tales of emotions and struggles" and "sweet, realistic romance between two people figuring their way in life."