To chat up some lady in order to fuck her.
Note the irony of that term : 4lifing (for life!) persons seek one night stands only.
Often used by Scouse and people who manage to cope with their slang and accent.
Mehdi : Danny is such a swine... he love to 4life sheilas who manage to get backstage... telling them the only thing that matters when life is over is "how much you've loved each other"... but just in order to get them laid and drop them the day after.
Arnaud : Yeah he's deffo a lying womanizer. But that's the kind of things people tend to forgive when you're a wanabee-rockstar.