Showdown! The Strongest Couple!!

is chapter 181 of the Beelzebub manga.

Summary
Oga and Hilda step up to the boxing ring for their round with the couple, Tanaka and Kawashima. However, Baby Beel realizes that Black Baby Beel is hiding within Tanaka's cap. Upon this revelation, Tanaka reveals himself as Saotome and Kawashima as Ikaruga. Ikaruga, after realizing that she has been uncovered, elaborately reveals that she is actually Saotome's wife. In the meantime, Saotome explains why they are competing in the tournament. Baby Beel and Black Baby Beel also end up fighting; Baby Beel is punched towards Hilda during the squabble and accidentally kisses Hilda, causing her to revert back to her original personality. Hilda prepares to leave until she learns about how the "real" Santa Claus will appear after a couple wins the tournament; afterwards, she becomes eager to participate for Baby Beel's sake.

Suddenly, the event for the two pairs is explained and set up in the boxing; both couples are forced to hold a balloon between each other while also trying to pop the other couple's balloon.

Once the event commences, both couples suddenly take their fight to the space above them. There, both males childishly fight with one another while the women verbally insult one another back-and-forth. The fight then becomes serious after Oga and Hilda are knocked back to the boxing ring, with Hilda using her Demonic powers to weaken the fall. However, Saotome and Ikaruga then begin utilizing Demonic power, resulting in an intense battle between the two pairs. Eventually, Oga develops a plan; together, he and Hilda use Baby Beel as a diversion while they secretly attack their opponent's balloon from behind. The strategy is successful, resulting in Oga and Hilda advancing to the next round.

Characters in order of appearance

 * 1) Tatsumi Oga
 * 2) Hilda
 * 3) Aoi Kunieda
 * 4) Kaname Izuma
 * 5) Shizuka Nanami
 * 6) Hidetora Tōjō
 * 7) Takayuki Furuichi
 * 8) Nene Ōmori
 * 9) Hajime Kanzaki
 * 10) Yuka Hanazawa
 * 11) Mitani (flashback)
 * 12) Oka (flashback)
 * 13) Beelzebub IV
 * 14) Suiten Ikaruga
 * 15) Zenjūrō Saotome
 * 16) Taeko Furuna
 * 17) Black Baby Beel