Hey dear, I personally believe very much in open communication even with our children. Kids will be kids but a 5 year old will be able to understand things pretty much. It old be advisable for you to gently explain to him your actions. Even in cases of other matters. For example, daddy hugged auntie as a form of greeting, at times we shake hands, give hugs to people closer to us or maybe even a friendly hug and kiss. Overtime your child will be able to understand. Exposure in communication is vital. Have fun Chit Chatting with your LO.
stop hugging out of courtsey...be the example ur son expects u to be. I'm surprised u r saying he's pulling your leg...and tht too a 5yrs old...quite an imaginative mind he's got there...