Sakura's rival who eventually became her close friend and ally, Syaoran had mixed feelings towards Sakura because his duty as a member of the Li clan of sorcerers from Hong Kong prompts him to be the inheritor of the Clow Cards. When Sakura becomes the official master of the Clow Cards, however, he changes his attitude completely and eventually ends up falling in love with her.
The teddy bear in the picture is quite significant with regards to their relationship. In the CCS world, if someone were to give a hand-made plush to the one he loves, and if she were to give the plush the same name as its creator, they are destined to be together forever. What happens in the anime and the manga are two variations of the same ending, but I wouldn't want to spoil it for anyone.
Pretty unique way of cosplaying Syaoran. I believe his costume is from another art illustration by CLAMP. Still very impressive though, wouldn't you agree?