It's from the Monogatari series. There's a lot of seasons, so it's complicated to know where to start off. The way I recommend watching it is in the spoiler: [spoiler]Nekomonogatari Kuro Bakemonogatari Nisemonogatari Monogatari 2nd Season Tsukimonogatari Owarimonogatari[/spoiler] There is a lot of fan service, but it's a legit anime. Probably the only one where I don't mind the constant fan service.