I like him , but my best friend doesn't want him for me :/ How do i say No?

I just gotten off of a relationship where my ex just wanted to get into the my pants. (i sitlL have my v-card). and my best friend really disapproved of him cause of what he always tried to do to me and doesn't want the same thing to happen again. i love my best friend very much and i understand how much she's just trying to protect me from guys like that & cares for me. and now, there's this guy who likes me name Mike and i like him too ! but ... my best friend doesnt like Mike cause he tried to get into his ex's (who is my best friend's friend) pants few months ago [i didn't know that !! o.o] Mike doesn't look like the kind either. Looks can really deceive nowadays. and aLso , Mike doesn't like my friends, so welL....that was kinda of a turn off. but yeah ! Mike really really really likes me and planned a doubLe date with me & his friends for tomorow night and keeps treating me even though i told him "it's okay :) i dont want you to waste your money on me." and he'll be like "C'mon, i know you want :D" and gives me the puppy face & i just give in T.T i know he'll ask me out tomorow at the movies, but i just don't know what to say ! if i say no, i don't want him to think that i've been leading him on :( and he'll get sad and won't talk to me anymore. and if i say yes, my best friend will slap me (she really does xD) and won't trust me anymore ):