In the Witcher 3's "Ashen Marriage" quest, set in Novigrad, Geralt assists Triss Merigold and her fiancé, Castello, with wedding preparations. His tasks include ridding the canals of monsters, procuring alcohol, and selecting a wedding gift for Triss. The gift's significance impacts Triss's response; a memory rose, a callback to Witcher 2, evokes a strong emotional reaction, while less sentimental gifts receive a cooler reception.
However, Dijkstra's revelation of Castello's connection to witch hunters throws a wrench in the proceedings. Castello's involvement stems from blackmail – the hunters threaten to expose his illegitimate daughter from a previous marriage.
Geralt can choose to reveal this truth to Triss, either alone or with Castello. Regardless, the wedding is called off. Triss is either disappointed in her fiancé or appreciative of his honesty, ultimately deeming the marriage premature.
This unexpected turn could have been further explored to deepen Geralt and Triss's relationship and provide more substantial character development for supporting characters.