Slagging is a term used to describe a kind of harsher form of teasing. While this may seem like an insult to some, to the Irish, it's considered a behavior that shows affection or bonding, and, in some cases, is even used as a compliment.
John:*falls down*
Patrick: Jesus, were you born with one leg shorter then the other?
John: Fuck off
Patrick: Calm down, I’m only Slagging you
a rather ugly female who is somehow capable of controlling a significant other and consuming all his resources (money, weed, time, etc.) by means of sucking a mean dick.
Man, Mike's really locked down with that Slaggerhoth. He pays her rent, smokes her out AND eats her pussy!!!!