I have a slim body and good looking face, but my calves are muscular and very big 15.5 inches, I cannot wear shorts just because of calves , now a guy is coming to see me , so should I tell him that I cannot wear shorts after marriage? Should I say to him shorts don't look good on me?
No. Don't bother. Just never wear them and if he asks you which he will in 3 years or so just tell him it's not something that fits you well and play it cool and move on. Don't even make it a conversation; he will try to focus his mindbits but due to the lack of intensity it will fail and he will just continue why you keep spending his money on your summer dresses that are at least twice what they are worth.
The guy should like you like you are, if he cares about you should not care
Honestly, your calves sound kinda sexy. Some guys like muscle-y legs; coupled with the rest of you, you are probably quite attractive. Wear the shorts just for him if you don't want others to see your calves. Go for a run or a bike ride or something with him to show off your legs - I doubt that he will care that they are large (most guys don't seem to care unless they like legs).