Your friendship will start out as a fascination between the two of you. Your friend has a compelling hold on your imagination, and you'll feel amazed by how deeply and how fast you get involved with them. This friendship will be a transformative experience, but be forewarned -- this will get intense.
If you're not into developing a true friendship with this person, you should let them know in no uncertain terms. Mixed signals could be interpreted in any way that they want, even if you've told them straight out that you don't want a new best friend. So just know this dynamic beforehand; that way, you can circumvent any jealousy or possessiveness issues that would otherwise become a problem. But if you're into developing a strong friendship, let them know. Honesty will get you far in this connection, and building a strong, supportive friendship is a very real possibility.