The phrase plays on Bienvenue chez les Loud, the French title used for the cartoon family the Louds, and swaps in Temu, the discount shopping name widely associated online with very cheap products. That single swap creates the whole joke: this is not the official version, it is the bargain alternative. French TikTok users picked up the expression as a shorthand label for drawings, costumes, toys and edits that look close to a familiar reference but noticeably cheaper, and it keeps circulating because the comparison is understood immediately.