Hatate Himekaidou from Touhou Project.
Remember the boba tea boob meme? The top left image is that except Hatate has no boobs and instead uses a super long straw :). Also she's wearing the "I have no tits" crop top. Obviously. She's perfect and she owns it. Ok, but she looked so good like that, that I thought "I Must draw her in casual clothes". After I finished the drawing I concluded that She is Too Lovely, and is My Girlfriend, hence the name :).
Coincidentally, about two months after drawing this, I met a girl that kinda looks like this, except she's not a lesbian. Now I'm dating her. What the fuck.