They don't have a relationship. Or, at least, that's what Kurt seems to think, and Puck doesn't really know how to tell the guy that they are in one and are going to stay in one for a fucking long time, and it's gonna be a couple-y and abso-fucking-lutely exclusive deal.
Because now that he's given in to his throbbing urges, there's no way back. There's no way that he can go and have somebody else when he's sunken his teeth on Kurt's perfect pale throat. He's addicted to the taste of his blood, to the keening noises he makes when he is trailing the last drops of blood from his skin, to the soft intakes of breath Puck earns to himself when he kisses the tender places where he's just bitten.
He's also addicted to an alarming extent to the way Kurt's scent spikes up in arousal, the way he flushes in pretty red and pink hues, the way his legs shake almost imperceptibly whenever Puck touches his groin or goes greedily down on him. Painstakingly –almost embarrassingly- addicted to the way Kurt's dick feels inside his mouth, to the bitter taste of his come, to the way Kurt's voice sounds beautifully wrecked when he's asking Puck to stop licking his limp member after ejaculating.
Puck wants him, needs him, and loves him. He is not sure that Kurt should have either a say or a choice in all of this.
But, well, life does not actually revolve around Puck's needs and desires and shit, which basically means that Kurt is allowed (and probably entitled) to his own opinion, and he thinks that they have some sort of friendship with whacky benefits and that he can go on with his life the way it had been before.
He can't. Because Puck can barely stand being away from him for more than a few hours at a time nowadays, sometimes –if Kurt happens to be away for the day doing something or the other with his girls- it gets to the point of physical pain, to the point where breathing is an incredibly hard task, to the point where he can feel blank spaces trying to bleach his brain –with voices, and smells, and other people's messy lives and emotions and touching, and fuck, hurts-.
He'd kinda hoped that finally having Hummel would've made everything better, the way La Maga had put it had made it seem like that was what would happen, that it would've somehow done something to his body chemistry to calm down the plethora of symptoms, but it hasn't. He still gets cravings and he still needs to touch the guy as much as possible, still needs to hear his thoughts -or whatever he can hear about them since anything from the boy that comes to him is all in shadows, blurred little forms, almost nonsensical sounds. Things he wouldn't understand if not for his uncanny ability to get anything about Kurt instantly- and his steady heart-beat near him. And it's maddening.
So, no, Kurt can't have his life the way it was before. Because as it is, Puck isn't going to have any normalcy in his own life any time soon, so why should Kurt be offered opportunities he isn't handed?
The thing is: the only plausible solution he can see is actually talking to Hummel, just up and going to him with all of these ill-advised words the feral thing (disease) inhabiting him keeps throwing up onto his brain, which he wants to avoid at all fucking costs, because it'd mean admitting both to himself and to the other boy that he's become a whole lot of things he never thought he'd become: sappy, in love, whipped beyond the point of recognition and dependent on his willingness to let him breathe his scent in, sink his teeth on him, and choke himself in every other sensation.
(And both bless –for stupidity- and curse –for stupidity- the little parts that battle against each other inside him saying either he should have anything and everything he wants just so he'll be happy at all times, including whatever kinda life he chooses with or without me or he should want this, with me.)
But that's not it. Since if it was, well, he'd probably grow a pair and fucking take it like a man.
There's in addition the fact that not only does Kurt seem intent in avoiding him as much as he can at all costs, but he seems, too, to be doing it out of a warped sense of moral obligation towards Puck.
Which, seriously, what the fuck?