The fulli version of a song is a fan-made extension (or loop) of said song. Fulli versions usually spring from TV animated series' OPs and EDs, where the insert songs are not yet (officially) released as the TV series was airing.

A full beer. Used when you have finished a beer and want to replace an empty with a full beer

Said to mean Really, Totally, Completely, a lot, very much so or to add emphasis to something.
Also said as an acknowledgement meaning O.K or I agree/concur. Said 'fulllllllleeeeee bro' in the west of Sydney or anywhere 'West' in Australia.

A fully automatic weapon

If ur not bout it or you get on someones nerves easily.

To see a woman's whole entire boob.

all those cans of beer that those drunk fucks opened and forgot were theirs after taking a sip and putting them down, they usually line beer pong tables and banisters and are abundant once the sun comes up