Bock (ボック Bokku) first appeared in episode 20 of Ultraman Leo.
Subtitle: Little Bear Sagittarius people (小熊座人 Koguma Zajin)
Pursued by Dogyuh in fireballs from somewhere in the Ursa Minor constellation after the fiend had killed his mother, Bock arrived on Planet Earth and disguised himself as a young boy to hide from the hostile alien. He befriended a young bear cub and met Gen, but showed him no ill will, merely leading him around, though didnt speak except his name. But as the alien left, readings Gen received began to drop off to nothing. The next day they found the boy with a bear cub and while they were talking, the villagers arrived, blaming the boy for the cause but as Bock fled, the cub was killed, causing him to prepare to sacrifice his life to stop the damage, as it turned out. Dan and Gen arrived, protecting the young boy, who mourned the death of the cub he'd befriended, his tears causing a black flower to grow. Soon, Dogyuh revealed himself for what he was and Dan attacked him to protect the boy. As Ultraman Leo was beaten down, Bock grabbed his flowers and threw them, causing them to grow into giant spears and impale Dogyuh's eyes, blinding him and then Ultraman Leo killed Dogyuh with the Leo Spark. After Dogyuh killed, Bock thanked Dan and Gen before he took off into the sky, now safe from the infernal Dogyuh.
- Cast: Nagisa Koyama
- His given name is a short for Koro-pok-guru, a race of small people in folklore of the Ainu people of the northern Japanese islands.
- This might be a reference to the boy's subtitle.
- Bock was the first alien to have been disguised as a human, but never revealed his true appearance.
- Height: 140 cm
- Weight: 28 kg
- Origin: Constellation Ursa Minor
- Powers and Weapons
- Human Disguise: Bock can disguise himself as young boy.
- Fireball Travel: Bock can travel through the galaxies with his fireball form.
- Flower Tears: Bock's tears can be cause the black flowers to grow.
- Black Flowers: After growing the flowers, they can be thrown as a spear.
- Flight: Bock can fly with a jet in his feet.
|Ultraman Leo Kaiju|
|Giras Brothers | Alien Magma | Alien Tsuruk | Kanedoras | Alien Karly | Kendoros | Vekira | Guiro | Ron | Alien Kettle | Bango | Alien Vibe | Antales | Alien Flip | Alien Atler | Alien Wolf | Bat Girl | Batton | Alien Boze | Bock | Dogyuh | Alien Alpha | Northsatan | Garon | Littre | Alien Coro | Renbolar | Carolyn | Alien Sarin Dodole | Gamerot | Alien Clean | Satan Beetle | Pressure | Oni-on | Planet Apple Chicken | Alien Paradai | King Paradai | Uriy | Uringa | Alien Magma II | Rolan | Alien Virmin | White Flower Spirit | Princess Kaguya | Kiraa | Alien Akumania | Ashuran | Sevenger | Taishoh | Alien Atlanta | Alien Mazaras | Specter | Alien Babarue | Black Directive | Silver Bloome | Black Dome | Absorba | Demos | Black Garon | Blizzard | Mayuko | Hungler | Black Terrina | Satan Mora | Nova | Alien Bunyo | Black End|