Check up about a vacuous gasbag being more annoying (7)

'more annoying' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'check up about a vacuous gasbag' is the wordplay.
'check' becomes 'rein' (both can mean to control or limit).
'up' says the letters should be written backwards (in down clue: letters go upwards).
'about' means one lot of letters goes inside another.
'vacuous' means to remove the middle letters.
'gasbag' with its centre taken out is 'gg'.
'rein' written backwards gives 'nier'.
'a'+'gg'='agg'
'nier' placed around 'agg' is 'NAGGIER'.

'being' is the link.

Can you help me to learn more?