Shinichi Nagata

He is Lyfas friend and mentor in ALfheim Online. He is skilled in concealment and high level dark magic. He harbors a crush on Suguha being her classmate in real life. He is key in investigating the Salamanders infiltration of the Sylph and uncovering Sigurds plot. He later rejoins Kirito and Lyfa at Aarun and urges Lyfa to leave and return to Sylvain after he finds her upset. Later he confesses to her and ends up getting punched. After Lyfa returns from meeting Kirito again she informs them they are attacking the World Tree. Source: SAO Wiki