My Dearest Self With Malice Aforethought

Eiji the college-age virgin dreams of someday having a girlfriend..until he wakes up one day with his "girlfriend" in his bed with him! Not only that, his buddy tells him he got in a fight..and that three days have passed that Eiji doesn't remember? What dark secrets are being hidden..by Eiji himself? (Source: Kodansha USA) *Note: Includes one extra chapter.*