A romantic relationship between two individuals with the intention of sexual gratification/procreation. The closest human equivalent is 'to be in love'.
A person in a matespritship may be referred to as 'matesprit'.
Also known as the flushed quadrant of the Alternians' relationship quadrants (MS Paint Adventures by Andrew Hussie).
Mates of State are an indie rock duo. Mates of State is composed of Kori Gardner (voice, electric organ, electric keyboard, and electric piano) and Jason Hammel (voice and drum set). The two are now a husband and wife team with a child.
To sell a product or service to someone at the same or close to what the product or service will cost you. Hence the person that you are selling to is being given a substantial discount on the normal price. As the term "mates rates" suggests this level of discount is usually only given to mates, or friends, of the person selling the product or service.
Bob: "Hey Johnno, how muchdid you pay for that computer?"
John: "Got it real cheap mate. Trev sold it to me at mates rates."