There's also this conversation regarding whether Geralt can give it up.
Dandilion crossed his legs and examined his worn sole with interest. “You remind me, Geralt, of an old fisherman who, toward the end of his life, discovers that fish stink and the breeze from the sea makes your bones ache. Be consistent. Talking and regretting won't get you anywhere. If I were to find that the demand for poetry had come to an end, I’d hang up my lute and become a gardener. I’d grow roses.”
“Nonsense. You're not capable of giving it up.”
“Well,” agreed the poet, still staring at his sole, “maybe not. But our professions differ somewhat. The demand for poetry and the sound of lute strings will never decline. It's worse with your trade. You witchers, after all, deprive yourselves of work, slowly but surely. The better and the more conscientiously you work, the less work there is for you. After all, your goal is a world without monsters, a world which is peaceful and safe. A world where witchers are unnecessary. A paradox, isn't it?”
“True.”
“In the past, when unicorns still existed, there was quite a large group of girls who took care of their virtue in order to be able to hunt them. Do you remember? And the ratcatchers with pipes? Everybody was fighting over their services. But they were finished off by alchemists and their effective poisons and then domesticated ferrets and weasels. The little animals were cheaper, nicer and didn't guzzle so much beer. Notice the analogy?”
“I do.”
“So use other people's experiences. The unicorn virgins, when they lost their jobs, immediately popped their cherry. Some, eager to make up for the years of sacrifice, became famous far and wide for their technique and zeal. The ratcatchers…Well, you'd better not copy them, because they, to a man, took to drink and went to the dogs. Well, now it looks as if the time's come for witchers."
During my conversation with Triss, Geralt also has the option of saying, "Can I still be a Witcher in Kovir?"
You can also say you'll give up being a Witcher and be a normal person.