Green’s Dictionary of Slang

beg v.

(UK black) to desire greatly; to humiliate oneself.

[US]BlazinParadise ‘Blazing Squad Language’ 🌐 Beggin – Sucking up. [Ibid.] Beg – To really want something.
[UK]T. Thorne (ed.) ‘Drill Slang Glossary’ at Forensic Linguistic Databank 🌐 Beg it– plead for favours, cringe before (someone).
Skepta ‘Nang’ 🎵 Peng ting, said she had enough of the fakeness / Told me she loves the way that I don't beg friend with any of them.

In compounds

begfriend (n.)

(UK black) someone who pursues friendship, but is not actually liked by their target.

Urban Dict. 11 Sept. 🌐 begfriend Somebody who follows somebody around but the person they are following doesn't even like them.
[UK]G. Krauze What They Was 96: I need someone to do eats with. But I’m not a begfriend so I wasn’t suddenly gonna ask him to bring me in on a move.