|Sarumen from the Eastern Forest|
|Manga Debut||Chapter 35|
|Anime Debut||Episode 41|
|Book of Friends|
|List of Characters|
They were youkais that came from the Eastern Forest wearing a monkey-like mask. Sarumen literally means monkey-face or monkey-mask. They captured Natsume to their forest, wanting the Book of Friends to save their lord of the forest, Rokka.
They wears large monkey-like mask, as mentioned by Madara, and wears white kimono. Seemingly because of their mask, they are much taller than Hinoe and the Chukyuu (A and B), as seen when the chukyuus were taken hostage to confront Hinoe and Misuzu, demanding for their friend back.
They first appeared after Natsume saved a goat-like youkai (Bearded Youkai) that got it's leg trapped underneath a boulder. They were physically threatening Natsume until he was saved by Nyanko-sensei.
Later on, they followed Natsume to his school and one of them suffocating Natsume in front of Nishimura. Natsume, realizing that they could harm other people if they stayed on the school's ground, lured them to nearby forest. However Natsume was captured and were brought to the Eastern Forest.
The other monkey-masked youkai were unaware that it was Matoba who had their friend. They instead accused Natsume of capturing their friend.
To lure Natsume from hiding, they captured the Chukyuu A and B as hostages. Afterwards, they found out that Natsume was also missing and it was the Matoba clan's responsible.
Two of the monkey-masked youkais searched for their friend at the Matoba's mansion. They found their friend and Natsume with Nyanko-sensei at the dungeon. They were furious that their friend was sealed in a pot and blamed Natsume for it. They tried to grab Natsume's bag, believing the Book of Friends was inside. However the sealed-away in the pot falsely claimed that he had checked the contents of the bag and the Book of Friends was not in it.