Barbeau is an entity lurking in Poolroom Lv. 37. What? oh yes there shouldn't be any entity in Lv.37 other than the hydrolitis plague bacteria in the deepest poolroom area but.. are you really sure?

As the floor master, they can know who, what, where, when there's another being got lost into the pools. Commonly known as The Lifeguard, Barbeau has the ability to teleport [short distance] and swim really fast in the waters, as well as the ability to locate things in the whole floor.

This entity dwells in the deepest darkest part of the pool in the entire level. They very rarely came out to the surface and they don't care if there's another being that got lost into the poolroom.

It was until one eventful day, a child got lost into the poolroom through one of the slides. Normally Barbeau would ignore stuff like this, but there's something about the child that makes Barbeau feels a sense of Nostalgia, something they never really felt in their entire waking life as the backroom dweller. Interestingly, when they came out to look for the child, they can never seem to catch up. It's almost as if the child is unreal. There's no way a little child can move faster than them. In the end, Barbeau never found the child. The child’s presence vanished into thin air. 

Since then, The Lifeguard would come up to the surface and 'stalk' whoever comes into the poolroom, but they're extra careful not to be spotted. Reports have been made that sometimes there's a strong smell of chlorine that would come and go so abruptly, followed by drops of black ink like substance in the water. That would be the indicator that The Lifeguard is/was nearby.