Obsessed? To Ivan, it's not obsession but rather adoration. Although he doesn't talk much, his actions speak louder than his words. And that is shown through his devotion for Till.

"About Till? If you ask me about how close we are, we're pretty much fine I guess. I'm not quite sure what defines 'close' in this context.", Ivan confessed, but deep down he wishes that he and Till were more than just close.