...I have seen no version of this canon at all so like, my entire knowledge of Geralt (and anything Witcher) is the memes people post on Facebook. Thus, I read your comment and mentally envisioned:

and I like working out how Geralt might come to care about Jaskier's feelings. Or pretending it's already happened and he just hasn't realized it yet

"Hmm."

...and imagining how he might realize it

"...Fuck."