In British English, "on a promise" simply means that you have arranged to or at least expect to have sex with someone in the nearfuture - usually your regular partner.
Sorry, Dave. No drinks for me tonight. The wife found the handcuffs we used on our weddin' night, so it looks like I'm on a promise, know what I mean?
Cigarette: Northern slang for a cigarette, used oft by mashed up mancunian ravers becasue of the resemblance of a hot(electric)stove to the end of a lit cigarette. Originated circa 1991 in the early halcyon days of the rave culture; we speculate during a drug fuelled hallucination by said manc.
'fuck me noel, i am bolloxed, is that a ciggy in your mouth, or the stove from me 'nans kitchen'/
General use: 'Give us a stove you cunt'
A hardo is a person who tries extremely hard at everything. Most times a hardo will try very hard at things that do not require excessive effort. For example, sports practices, gym class, etc.
Wow did you see Jack at practice today? What a hardo!