Everything is a misadventure with baby Masanori.
Hairu and Ui first learned he could crawl when he disappeared from his room one night. As Ui melted down and called Arima in a panic over their kidnapped child, Hairu found baby Masanori in the bathroom. He was splashing toilet water.
His first word was “mwah.” It’s what Auntie Eto told him to say.
Masanori’s first sentence was “I love you,” to his daddy. Ui melted and Arima (after a poke from Eto) told Ui he was proud of him.
He once decided to give Mommy a haircut. She woke up to her bangs snipped off with scissor. Hairu was more upset that she had to wear her hair different than Ui than she was about the actual haircut.
Masanori once tried to convince Auntie Eto to give him human flesh to eat. Just to try it. Ui nearly passed out and Hairu was pissed.
When he grows up, he wants to be Uncle Uta or Uncle Shio.
His favorite day of the year is his birthday, because Uncles Shio and Yusa, and Auntie Rikai, play water balloons with him. Next year he’s planning to rig traps that dump dozens of balloons on his enemies at once. Hairu encourages this, and Ui will be helping build the traps. It’s only fair because Hirako is preparing the rest of the Zero Squad kids.