Maybe he wants to let you know his feelings for you or he wants you to love him too or he just want to get your attention.
What Does Mean When Guy Texts Luv U?
He wants your attention or hes just messing with you AS A FRIEND...I do it all the time to both girls and guys who are just friends. I dot know what this guy is to you but he might actually love you...I don't know
Ugggghhhh my friend took my phone and txted I luv you to my crush and he was like what r you talkin bout I was like just a joke