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
When a female gets sexually aroused by a person of the opposite or same sex to the point where they cannot control their vaginal fluids and they create a "trail" as they go about their day to day activities.
Susan thought Timmy was so hot in his manktop that she was sluggin' through the hallways at school.