Board Thread:New on Sword Art Online Wiki/@comment-70.31.107.95-20161226054139/@comment-69.136.213.200-20170304164959

"Close" does not mean "romantic interest". He naturally cares about the other girls since they are his friends, but keeps it at a platonic level and they are fully aware of it hence why they don't interfere with Kirito and Asuna's relationship. Whereas Kirito makes it perfectly clear that he loves only Asuna to the point that he has sworn his life to her.