They dressed shabbily and speak mostly vulgar and abusive language. Atsara are witty, lewd and salacious. Sometimes they are very annoying and bothersome, but without them a tshechu would look dull. Their pricy possession is the phallus which is lavishly used.
Having said that, I am not at all undermining the Atsaras and making fun of it. Rather I want to highlight their importance as many would not know other than their witty behaviors.
Atsara is derived from the Sanskrit word Acharya which means holy teacher or dubthop in Dzongkha.
According to Buddhist history there are 84 dubthops (Mahasiddhas), an enlightened beings who had extinguished all their defilements and afflictions. These Dubthops roamed all around to subdue evil thoughts by mocking worldly things. They used their wit, foolery, and drollery, together with their powers to uproot evil from the minds of mortals.
Atsara represents these enlightened beings. Their apparent vulgarity arises out of their detachment from human feelings like embarrassment, hesitation, and reservation. Their vulgarity behaviors is with a purpose to remove your embarrassment and reservation.
Atsaras are therefore a spiritual figures at the tshechu who carry the blessings of 84 dubthops to propagate Buddhist teachings. Besides, Atsara have a big responsibility. They are the guides for the mask dancers and also for the spectators.
So next time when you see Atsara, treat them as representatives of great Mahasiddhas.