Meru is a character and featured as the main antagonist from the anime movieKeroro Gunso the Super Movie 2: The Deep Sea Princess and the only known Maronian along with Maru from Maron. He is voiced by Hoko Kuwashima.
In the second movie, he, together with his counterpart Maru, defeated a Kiruru that tried to destroy a ship then he begins humming beautifully for saving the ship and he appears in the sky (as a shadow figure) along with Maru and they flew down, off screen. He appeared as a "sea fairy" in a ball of light.
He watched Natsumi through the "UMA", which Momoka brought to Fuyuki. Later, sea creatures brought Natsumi to Meru. He appears to be a bit childish as in Natsumi's dream world, he played a lot.
He sang to Natsumi, then used the Mare Ball, transforming into a more human shape and hypnotizing her.
When Maru opened the door to him and Natsumi, he had grown immense, with Natsumi held hostage to his body. He used the Mare Ball and threatened to attack Keroro and Fuyuki, when Mois saved them by attacking the attack. Keroro asked Fuyuki to throw him into the cystal before it closes, which was successful. But, it disturbed Meru's process, and he turned even larger, controlled by the Mare Ball. Keroro was seen on his shoulder.
When Momoka, in Keroro robot, was going to attack, he attacked back, which was protected by Mois again. But, the beams went into all directions, flooding the entire place since he broke the barriers. When Maru asked him to release Natsumi, he refused, and destroyed the shopping mall, which shook Natsumi to a bit of her senses.
Meru is dark-blue colored. Unlike Keronians, He wears dark blue helmet with short ear-like crests and a bigger crest on his head. His symbol is a yellow Maron star on his forehead and on his belly. He has dorsal-like fins attached on his wrists and limbs and his eyes are triangular and its colored bright green and wearing a yellow collar on his neck.
Meru is somewhat very strict, and has a spoiled brat attitude towards Maru for troubling him, blaming her for distracting his talk, and thinking Maru that it was her fault for losing him (but Meru is the one who made Maru lose him) in the shopping mall during the chase for fun. Meru is seen snooty and mean at first when he confronts Keroro, calling him rude and boring. Meru is also very kind, calm, and proud towards his princess, Natsumi.
- Maru - Childhood friend, and now princess and right-hand. She was very loyal to Meru, supporting him in all his commands. When he yelled for help, Maru flew right in, and was sucked in. She managed to hold his hand, as he was slowly turned back to his original form surround in red aura with the Mare Ball in his hands.
- Natsumi - "Princess", whose dream world as created by the Mare Ball.
- Keroro- Meru thinks that Keroro is very annoying and a waste of space and time and Meru thinks Keroro is boring.
- Fuyuki Hinata - In Volume: 20 of the Manga (which was a full scale reboot of the 2nd movie) close to the end of the story it is revealed that Meru had developed a "Hero Worship" to Fuyuki back when he was a little kid and constantly took on the physical appearance of little Fuyuki.