NOTE: This article contains spoilers! Read with caution.

Semi / セミ
First Appearance: Vol. 8, Ch. 56
Status: Active
Race: Lunarian
Occupation: General

Semi (セミ), translated as Cicada in certain fan translations, is a Lunarian. He has become acquainted with Phos while they are on the Moon and accompanies them both when they return and when they come back with the other Gems.



Semi's form while fighting.

On the Moon, Semi is a hulking person with a wide upper body. He is much taller and larger than normal Lunarians. He has thick, short eyebrows, short hair, and rounded features. Like other Lunarians, he has small rabbit ears on his head.

When on the planet in combat, Semi takes on drastically different appearance of a much larger, intimidating creature resembling a demon or ogre. Whereas before, he appears more round and soft, in this form he appears well-toned and very muscular. He wields a vajra, a type of club that symbolizes the indestructibility of diamond and the unstoppability of lightning. While in this form, Semi proves to be a very dangerous threat to the Gems, holding his own against even Bort.


Semi has a soft personality; he is very friendly, behave in an upbeat manner, and worries about the well-being of others a lot. Unlike most Lunarians, who have been shown treating Gems in an objectified manner, Semi shows Phos kindness and concern.

He is somewhat unintelligent and clumsy though, making slips of the tongue and not being able to explain how things work. When he first met Phosphophyllite, he was unable to remember and speak their name. He later accidentally reveals Prince Aechmea's name to Phos, causing him to immediately cover his own mouth in surprise.


After Phosphophyllite infiltrates the Moon and is accepted as a guest, Semi was sent to greet them when they woke up after their first night on the Moon. He tells them that he will be observing them, though he quickly corrects this to mean that he will be serving them. He takes Phos on a tour of the Moon, including various facilities such as the synthetic gem factory and the experimental facility for creating humans. He is unable to explain how they work though, and instead reads information from a pamphlet (written in a language foreign to Phos).

While at the experimental factory, Phos complains of feeling unwell, and Semi agrees, saying that he does not like the strange music that always plays there. They take a break and Semi snacks on something that resembles a cookie. During this time, Semi accidentally reveals the Prince's name to be "Aechmea". He tells Phos to keep it secret because Prince Aechmea is embarrassed of that name. Semi then says he cherishes his own name because it was given by Prince Aechmea. He tells Phos that all the Lunarians love and respect their Prince, reminding Phos of the same way the Gems love Kongo-sensei.

Afterwards, Phos comes up with a plan to aid the Lunarians and betray Kongo. They speak with Aechmea using his real name, causing Semi to cover his mouth and apologize to the Prince, though he easily dismisses it. Semi escorts Phos back to the planet on a sunspot, hugging them before they leave. When they reach the Land, Semi comes out in his combat form and fights Bort, skillfully deflecting their attacks to the surprise of all the Gems. But they quickly disperse once Phos was returned to the Gems.

Sometime later, Semi revisits Phos under the guise of another Lunarian attack. He came to check on Phos and talks with them using a specially designed "battle talk-stick" that allows him to speak in the planet's unbreathable atmosphere. They allow Phos to disperse them after confirming everything is all right.

Phos had agreed to bring back some of the Gems to the Moon after a month. When the time comes, Phos leads a few of the Gems to the Lunarians, including Semi, who await them at the beach. Semi carries the casket where Padparadscha sleeps and all the Gems depart on the Lunarian's transport vessel. During the flight, Semi allows the Gem to touch and feel how soft he is.


Like the other Lunarians, Semi is loyal to the Prince. Aechmea considers Semi a softie, relenting and creating a device to allow Semi to talk on the planet when they go to check on Phos. Aechmea refers to Semi as "General" so it can be assumed that he is a higher rank among the Lunarians.

Semi quickly grows attached to Phos, going to check on them and showing great concern about their safety when they return to their planet.


  • The kanji characters used for Kongo's name are 金剛, which may also mean vajra, the same term for the weapon that Semi uses.
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