My boyfriend was not keen on having pets as we live in an appartment, but I slowly worked on him and for my birthday the presented me with a 'gift certificate' allowing me to go out and get whatever fish tank my heart desired....so I flipped it around a little and told him that a terrarium takes up no more room than an aquarium and snakes are interactive, you can actually handle them whereas I don't think the fish like being stroked....He was really strong and stuck to his guns for a while but it was mainly feeling uncomfortable around reptiles that was the issue, so I took him to a local exotics zoo and asked the owner Frank, to let Thomas play with a cornsnake. After 2 minutes, Thomas' comfort level rose from about 2/10 to abot 6/10 just because that whole 'fear of the unknown' had been taken away. Also, he always has thought that snakes with slit pupils looks nasty and he likes the cornsnakes round pupils...fast forward to about a month later and we attended a reptile show and came home with Alka and Seltzer!
Those first 2 were joined by Mylanta (who turned out to be Myls!) about 2 months later and these days we're up in the 30's somewhere!