crush asking who else i like?

so, my crush knows i like him and so does half the grade. he txted me and said "who else do you like besides me?" i kept asking why and he kept saying beacuse. hes my best friends cousin and she says i should tell him but idk. im scared he will tell someone. i know he doesnt like me but i dont know if i should tell him. please help! he keeps texting me!