ホウセイマイフレンド
A joke in [[Downtown no Gaki no Tsukai ya Arahende!!]]'s 2013 New Year's Eve Special: "Zettai ni Waratte wa Ikenai Chikyuu Boueigun 24ji (2013)":[https://ja.wikipedia.org/wiki/%E7%B5%B6%E5%AF%BE%E3%81%AB%E7%AC%91%E3%81%A3%E3%81%A6%E3%81%AF%E3%81%84%E3%81%91%E3%81%AA%E3%81%84%E5%9C%B0%E7%90%83%E9%98%B2%E8%A1%9B%E8%BB%8D24%E6%99%82].

Here's a good English explanation: comment #1225449.

Here's another one:

[quote]Reference to the 2013 instance of the annually recurring "Absolutely No Laughing" segment on the long-running TV show "Gaki no Tsukai":[https://en.wikipedia.org/wiki/Downtown_no_Gaki_no_Tsukai_ya_Arahende!!], which was called "Absolutely No Laughing: Earth Defense Force". Part of the skit involved an alien being discovered in a cupboard, which suddenly decided to declare its eternal friendship with "Tsukitei Housei":https://en.wikipedia.org/wiki/H%C5%8Dsei_Tsukitei by saying "HOUSEI MY FRIEND" (in English). Eventually this caused Housei to be branded as a traitor to Earth, when the alien invaded an Earth Defense Force base, was captured, and indicated that Housei was its friend. Full story "on ニコニコ大百科":[http://dic.nicovideo.jp/a/%E3%83%9B%E3%82%A6%E3%82%BB%E3%82%A4%E3%83%9E%E3%82%A4%E3%83%95%E3%83%AC%E3%83%B3%E3%83%89], abbreviated video clip of the segment "on YouTube":[https://www.youtube.com/watch?v=2Jcps_TM7bc].[/quote]
housei my friend