well..your friend or acquaintace did joke with you, I guess. prob you said 'I love you or 알라븅(very much spoken language term which sounds 'I love you' in funny and cute way. 알라뷰=I love you but funny way, in normal way '아이 럽 or 러브 유', -+o(-ng- ending sounds makes funnier and cuter usually in spoken korean form) "나는 안 알라븅!" so that sentence means 'I NO luv you'(if we make that sentence in Eng, it looks like it) which means 'I dont love you.' hope it could be helpful for you. if you have further question, please ask again. :) thanks