Jaskier chokes at the mere mention of illegitimate children, which... well, is probably quite a concern for him, because of all the philandering. If there is one single good thing that ever came from the witcher mutations, it's Geralt's sterility-- no bastards for him, thank you. And perhaps the immunity to disease. The witcher remembers without fondness an unfortunate dalliance of Dandelion's that resulted in him having... an unwanted gift from his paramour in the form of the clap. He'd complained incessantly until they found an appropriate healer who could cure him.

Geralt is sipping at his wine when the bard refills his own glass and notices the label for the first time. He's almost pleased to note that Jaskier has the exact same reaction to the bottle as Dandelion did when he saw it-- eyes wide, mouth open in indignation. Clearly, whatever he had expected to see on that bottle, it hadn't included the moniker that he'd spend the past few decades trying to get rid of.

"It's a bottle of wine, Jaskier," he replies, knowingly and willingly being a shit. "It's from the Belgaard vineyard, you can tell from the crest, right there."

He points at the bottom of the bottle's label, where the coat of arms of the vineyard in question is drawn, along with its bottling year. He's being very helpful right now, isn't he, Jaskier? Providing information.