The double bite is a physical attack inspired by the terrifying second jaw of moray eels. They grab ahold of the prey with their main jaw and essentially yoink the prey down their throat with their extremely fast second jaw, which helps them eat larger fish than one might expect.
The first stage of the attack, the first bite, would reflect this by being less powerful than the secondary smaller attack which, whilst doing extra damage, also stuns the target for a small amount of time.
Fun fact! Moray eels are the only animals with this type of jaw situation, and might remind you of a famous extraterrestrial :)
