Masao Maeda

Masao Maeda (前田 まさお) is a minor character of Demon Slayer: Kimetsu no Yaiba. He is a member of the Kakushi, the support unit of Demon Slayer Corps, and works in the Sewing division.

Appearance
Masao is a young man of average height. He wears a pair of large round glasses to help him see. Most of his features are blocked by the head covering and the mask all members of the Kakushi adorn.

Personality
Within the Demon Slayer Corps, Masao has gained a negative reputation for his inappropriate behavior and is widely regarded as a pervert. He has earned the derogatory nickname "Scum Glasses" due to his actions, which include creating sexualized uniforms for female Demon Slayers and harassing them.

When questioned about the revealing outfits, Masao would manipulate and gaslight people, convincing them that they are normal and official attire, as he did with Mitsuri Kanroji. He also deny any allegations of tampering outfits, such as when he was suspected of making Kanao Tsuyuri's culotte panties slowly shorter and shorter, dismissing such claims as baseless and attributing any perceived changes to the viewer's own lewd perspective.

In moments of confrontation, he would speak rapidly in an attempt to extricate himself from the situation, displaying a deep fear of potential escalation, particularly if Sanemi Shinazugawa is involved. This fear stems from a past incident where Sanemi admonished Masao for his misconduct, causing him to experience intense fear and even wet himself. When Shinobu destroyed the uniform he had made for her, Masao humbly prostrated himself on the ground in a gesture of remorse and apology.

History
After successfully passing the Final Selection, Mitsuri was presented with a Demon Slayer uniform by Masao, who had secretly designed it to be revealing. Confused by the ill-fitting measurements, Mitsuri expressed her concerns, but Masao assured her that it was perfectly normal. Although she found the outfit embarrassing, Mitsuri believed there was nothing she could do about it. Shortly after, Kyojuro Rengoku gifted Mitsuri a white haori to commemorate her official induction into the Demon Slayer Corps. Mitsuri tried it on over her Corps uniform. Kyojuro was taken aback by the revealing outfit and questioned Mitsuri about its nature. Senjuro Rengoku, not fully understanding the implications, asked if it was a customary uniform for Demon Slayers. Flustered, Mitsuri explained that Masao had assured her it was official, causing Kyojuro to drop the matter.

Upon becoming a Hashira, Mitsuri attended a Hashira meeting where she encountered Shinobu Kocho, who was wearing a non-revealing uniform. Feeling deeply embarrassed, Mitsuri exclaimed in panic that she had believed that all female Slayers wore the same uniform. Her panic reactions annoyed Sanemi, who was also present at the meeting. Shinobu revealed that she too had received the same costume from Masao but had burned it in front of him. She had also provided matches and oil to Kanao and Aoi, who had received identical outfits.

Trivia

 * Masao only shows up in extra pages of several volumes and in a spin-off. He never appeared in the main chapters of the manga. Yet he’s well known among Japanese fans since his nickname had a strong impact.