Ghost of a flea

Neat story! But I really really doubt the authenticity of it. First of all, no indication of aircraft type, registry, or even minor details about the airline (major Asian carrier or North American carrier, for instance). It's obviously something big enough for medium- or long-haul routes, hence the crew rest area.

The second and pretty much bulletproof point is that aircraft bathrooms are incredibly tiny and cramped. They are typically on either side of the aisle and this gives them low, curved ceilings and very, very little headroom. There is simply no room for a man or woman of average height to hang themselves, and no fixtures on the ceiling which might make it possible -- unless the person had the foresight to bring a battery-powered drill, rope, and pulley. You'd have to drill through the inner cabin ceiling into an aluminum support structure, screw the pulley into the fuselage structure, then knot the rope, hoist yourself into the air, and tie it off on something sturdy like one of the sink fixtures.

I quite agree!