An insignificant yet noxious little stain that refuses to go away or recognise when it has been bettered. Usually to be found latched onto something with more substance than itself (easily found), the Twatl will try to impress with bravado and bolshiness, using inane babbling to attempt to cover it's very limited sphere of knowledge.
Unfortunately this will, ultimately, result in the Twatl looking more like a penis than ever before.
Its bipolar nature complicates the situation with a leading professor in the field describing the Twatl as "a mong leprechaun, dancing around a paper toadstool, offering wanker handshakes one second and flinging shit the rest."
The Twatl has an irrational fear of what it describes as "internet hard men" (although a more accurate description would be "fellow internet users who actually know their arse from their elbow") which leads the Twatl into round after round of ever more delusional and contradictory self repetition.
The Twatl has been proven time and again to be an arsebiscuit of the highest order, yet finds itself hugely amusing. Some suggestions from the scientific community put this down to it's latchees "putting it up" to make a fool of itself for their own sadistic amusement. This, of course, is something that goes way over the Twatl's head and only serves to encourage it to unprecedented heights of self destructive behaviour.
Further investigation into the Twatl's nature has proven difficult as researchers will often pass out after observing the subject for a short while. It is entirely possible that, with more exposure to the Twatl, we could find the first ever example of death by boredom.
Suffice to say someone behaving as described above is a Twatl