A scrubby fucknugget is a person who is a fail in life, has no friends, is untalented, and is a straight up loser. They are scrubs, dress like scrubs, and act like scrubs and they are just idiots like scrubs. These people are typically social pariahs, and can't get a date.
Andrea is a scrubby fucknugget cause she is sitting all alone at that lunch table.
A person who is a nub that spends their time doing pointless things. They have no life and they tend to be losers (fucknuggets).
Andrea, you are such a scrubby fucknugget for spending the whole day doing homework.