He is affected, there has been a woman or two that made him go woozy and find her downright irresistible, like when he went to get a shot or something that should help with his condition, at first all was normal, she had taken precautions to certain extent that she could at least somewhat resist, but then they both just lost it and what happened next? Sex xD
And I don't know, it might be that the effects of the whatever they did to him are rapidly growing too I think, at least it seem that way, and who knows what other symptoms and effects there may still be that hasn't triggered or are just now starting to come in effect.
He isn't taking advantage of anything and certainly not of his condition, he's not a douchebag and besides, he could get ladies without it, so it's not like he'd HAVE TO use his condition to do anything. Besides, if he wasn't concerned or if he didn't care and if he didn't want the effects removed and such, you think he'd care to find away to get rid of it? Not really