That is the IKEA POÄNG Armchair. A chair that's been part of their catalog for a very long time.
It's well known for being the chair featured in the endless sitting machines that used to be in stores all over the world about a decade ago to demonstrate its durability.
YouTube: #28 Durability testing of the Ikea Poäng chair

It has some special history for the Japanese audience, when one broke on live television when two comedians were screwing about with one, which probably is what this post is referencing with the right leg snapping.
YouTube: Unbreakable Ikea Chair Breaks on Japanese Live TV