One of the girls I have a blowjob to recently suddenly calls, and says she wants something serious(commitment) with me, out of the fucking blue. Saying stuff like " I want sth serious and not just seeing each other "

I said : we haven't seen each other ever since that day, what?

And the blabbering from her continued. OK guys roast me on this one too I don't know how to fucking handle, I can't and I don't want to go serious with her. How do I avoid any conversation with her about commitment and keep her on my side for free blowjobs?