Help!

So I'm looking for this manga, but I don't remember much about it. Hope you guys can help.
There were two guys and I know one for sure had this radar that he could tell whenever the other guy was close to him. At the end they meet at the top of this high rise or some other tall building and the guy with the radar loses the ability because (since they're both together now) he no longer needs it. Hopefully someone knows the manga I'm talking about! Thanks!!