Irrational Decision!!

is chapter 219 of the Beelzebub manga.

Summary
High above Ishiyama High School, Saotome is confronted by a duo from the Solomon Company who inform him about how his presence has affected their plan. He scoffs at the two and coldly tells them that he does not care whether they want him as company or not, while he conjures an orb-like Spell from his hand.

Udagawa wonders in the meantime whether he should make an escape now that he has been cornered by the students of Ishiyama.

Fortunately, Takamiya manages to break free from the underside of the pool and stand on his feet; his immense endurance and perseverance bewilders the other teenagers around him, including Oga. Oga calls for Baby Beel to get off of his back and goes to confront Takamiya on his own, subsequently engaging in a traditional fist-fight like they both planned for.

While watching the fight, Udagawa makes an attempt to escape but is cornered by both Kanzaki and Himekawa. Udagawa suddenly asks them in astonishment as to how they could let Oga fight against Takamiya on his own. Himekawa explains to the confused Udagawa, whom he adds could never be one of their allies if he truly does understand why their leaders are fighting, that the sole reason behind Oga's and Takamiya's personal battle is the fact that they are simply men; as he speaks, his subordinates suddenly begin crying as they watch the fight.

Eventually, Oga and Takamiya's battle finally ends with a simultaneous punch from both men that leads to Takamiya finally collapsing; before he collapses with defeat, Takamiya admits to Oga that he is a very good fighter. Meanwhile, Aoi has fused the two pieces of Furuichi's "soul" that she forced out from Ogata and Suzune which subsequently results in a miniature Takayuki Furuichi; unfortunately, he begins asking her a variety of questions regarding her attire which wears her out mentally. The two then meet up with Tōjō who points them to the direction of the pool, where they see Oga standing victorious over a defeated Takamiya while the Himekawa Special Forces cheers on the former. Aoi becomes enlightened by the victory before her own eyes.

Even Saotome comments on Oga's victory. He boasts to the two Spell Masters, both of whom are now restrained midair due to one of his Spells, that they fought their battles with the wrong group of people; however, he is told that their organization's plan is actually going into full course while he speaks, surprising him.

A young individual approaches the teenagers on the poolside with melancholic cheerfulness, telling Takamiya that he is no longer needed.

Characters in order of appearance

 * 1) Mitch
 * 2) Zenjūrō Saotome
 * 3) Akinori
 * 4) Tatsuya Himekawa
 * 5) Shintarō Natsume
 * 6) Kaoru Jinno
 * 7) Hajime Kanzaki
 * 8) Yōken Udagawa
 * 9) Shinobu Takamiya
 * 10) Tatsumi Oga
 * 11) Beelzebub IV
 * 12) Yuka Hanazawa
 * 13) Aoi Kunieda
 * 14) Takayuki Furuichi
 * 15) Hidetora Tōjō