Im really confused about my "straight" friend?

okay its been like this for a while but its begun to get a little more akward , in my lgbt theres a guy named daniel hes "straight" and is with my friend lauren ,shes bi and he comes to support her , he always flirts with me ,hes always very intimite around me , like whenever hes around me he will hug me and feel me up , and they say hes only being friendly , as time went on he became more comfertable with me , and he groped my crotch before and he always trys to grab my *** and is always feeling me , he acts like were with eachother , and hes always says stuff like " i love you " and " hey babes" and "i want your *** " and "you sexy beast" , each time we would see eachother he became more closer to me , infact hes until he met me everybody said he was always quiet and now hes not when hes around me , bu hes "straight" whch is what confuses me , and ive just ignored it until on saturday when we were all at pride cause we were in the parade , he said "today i have permission to be gay today , and im gay for you " and then he held my hand walking in the parade , he actually kissed me aswell at the concert afterwards , which i was shocked , and i know a straight guy doesnt do that , and im afraid to tell anybody or ask anybody , i do really like him , hes so cute and hes so comfertable around me , but i dont know what to do , he also has a girlfriend so im really confused , any help please