My Friend's a Monster (ともだちは怪獣 Tomodachi wa Kaijū) is the seventeenth episode of Ultraman X.
Sakura and her mother had just moved to a new house, which was rumored by the neighbourhood for a red ghost sightings. Sakura witnessed a monster, which likely based on the red ghost interpretation but dismissed by her mother and continues her work.
At the Operation Base X, Xio just recovered a briefcase of Spark Dolls (Saramandora, King Crab and three others unknown), which began to surface after the Dark Thunder Energy's appearances. While Daichi brings the Spark Doll to the lab, the Lab Team members tried to use Guruman as a target to attract the Dark Thunder Energy, believing that certain monster cells, as well as Spark Dolls are equivalent to "lightning rods".
The next day, after returning from school, Sakura finds a small bouquet of flowers at the front door and spots the monster from before, learning its name as Pigmon and plays with it. That night, Sakura asks her mother if she can keep a peaceful monster as a pet which the latter agrees, thinking her daughter was joking. After a day playing with Sakura, Pigmon returns to its home at night, placing the headress made by Sakura beside several toys before put to sleep.
Sakura and her mother prepare to leave for shopping mall and during that time, Pigmon sees a dark cloud and the city below it, Tatara City, proceeding to chase Sakura's car. Pigmon arrives at the shopping mall as well but accidentally invokes panic at nearby citizens due to its appearance. By the time Xio officers arrive, Pigmon had already tied and placed with a balloon on it. Several civilians deemed it as a threat except Sakura, knowing it meant no harm. Guruman recognizes the monster, having mostly spotted in Sydney, Australia and Luxembourg. The effect from the Ultra Flare may had awaken them as a result. Pigmon awakens and jumps in fear but misunderstood for rampaging which made a civilian attempted to attack it. Daichi analyze the monster through Gao Diction and finds it fearing of "something".
But it was too late for Pigmon: the Dark Thunder Energy strikes the Tatara City and brings forth a green fish monster, identified by Daichi as Guesra's variant, King Guesra. The man whom attacked Pigmon before was about to be crushed from several falling rubble until Pigmon saves him, at the cost of its own. X arrives on the scene and tries to fight King Guesra, but its poisonous scales and barrages of thorn attack overwhelms X, even the Bamstar Armor is easily penetrated. X finally uses the Exceed X form to cleanse King Guesra from Dark Thunder Energy before turning it into a Spark Doll via Xanadium Beam.
Pigmon seemingly dies from the injury as Sakura mourns over its loss. According to Daichi, ever since their awakening in the Ultra Flare, Pigmon would always seeks children as their playmate and due with most of them leaving for adulthood, they would wait again till new friends would come. While several civilians clean Pigmon's shelter, Sakura returns from her school again and finds Pigmon alive, as Xio had temporarily placed it under their care for medical treatment before releasing it to Sakura.
Daichi's Monster Lab
- Daichi: Daichi's Monster Lab! This time, we're looking at this monster!
- X Devizer: Now analyzing Pigmon.
- Daichi: The friendly rare beast Pigmon, they are small and cute but will risk their own safety at times to protect people. Its a monster with courage to spare.
- X: And this time we're showing you Pigmon's card.
- Daichi: Being strong isn't just about winning fights. The kindness that lets him befriends humans must be its true strength.
- Daichi and X: See you next time!
- Daichi Ozora (大空大地 Ōzora Daichi): Kensuke Takahashi (高橋健介 Takahashi Kensuke)
- Asuna Yamase (山瀬アスナ Yamase Asuna): Akane Sakanoue (坂ノ上茜 Sakanōe Akane)
- Wataru Kazama (風間ワタル Kazama Wataru): Yoshihiko Hosoda (細田よしひこ Hosoda Yoshihiko)
- Hayato Kijima (貴島ハヤト Kijima Hayato): Ukyou Matsumoto (松本享恭 Matsumoto Ukyou)
- Mamoru Mikazuki (三日月マモル Mikazuki Mamoru): Hayato Harada (原田隼人 Harada Hayato)
- Rui Takada (高田ルイ Takada Rui): Haruka Momokawa (百川晴香 Momokawa Haruka)
- Takeru Yamagishi (山岸タケル Yamagishi Takeru): TAKERU
- Chiaki Matsudo (松戸チアキ Matsudo Chiaki): Chiaki Seshimo (瀬下千晶 Seshimo Chiaki)
- Sayuri Tachibana (橘さゆり Tachibana Sayuri): Sarara Tsukifune (月船さらら Tsukifune Sarara)
- Shotaro Kamiki (神木正太郎 Kamiki Shōtarō): Yuu Kamio (神尾 佑 Kamio Yū)
- Ultraman X (ウルトラマンエックス Urutoraman Ekkusu): Yuichi Nakamura (中村悠一 Nakamura Yūichi)
- Alien Fanton Guruman (ファントン星人グルマン Fanton Seijin Guruman): Yasunori Matsumoto (松本保典 Matsumoto Yasunori)
- Xio equipments, X Devizer: Hibiku Yamamura (山村 響 Yamamura Hibiku)
- Ultraman X (ウルトラマンエックス Urutoraman Ekkusu): Sakaekei Iwata (岩田栄慶 Iwata Eikei]])
- Alien Fanton Guruman (ファントン星人グルマン Fanton Seijin Guruman): Hiroyuki Fukushima (福島弘之 Fukushima Hiroyuki)
- King Guesra (キングゲスラ Kingu Gesura): Kazunori Yokoo (横尾和則 Yokoo Kazunori)
- Pigmon (ピグモン Pigumon): Satomi Maruta (丸田聡美 Maruta Satomi)
- Ultraman X
- Ultraman Exceed X
- The main episode's setting, Tatara City is a reference to the Tatara Island from episode 6 of the original Ultraman. That island was where Pigmon first spotted.
- An allusion to the original Pigmon is that this also shown tied with a pink balloon.