Kamen Rider Den-O + Shin-O is the title of a special episode of Crayon Shinchan initially played as part of a full hour special titled Crayon Shin-chan Midsummer Night: I Have Arrived! The Storm is Called Den-O vs. Shin-O 60 Minute Special!! that aired on August 3, 2007. It featured a crossover between Shin-chan and the tokusatsu series Kamen Rider Den-O, as well as three normal summer-themed episodes. The Den-O characters are drawn in the style of Shin-chan's regular characters.
When Misae is trying to get Shin-chan ready for the bus on time, he suddenly has to go to the toilet. As Misae pleads to him to hold it in until he gets to school, Shin-chan manages to get inside, but instead of the toilet he finds himself on the DenLiner and on Ryotaro's face. He quickly becomes smitten with Hana and Naomi, much to their chagrin, while everyone tries to figure out why Shin-chan has managed to get on the DenLiner. Back in the Nohara house, Misae bangs on the door as the Fatass Imagin tries to grant Misae's wish, which is to get Shin-chan to the bus on time.
Back on the DenLiner, Hana realizes that it must be due to an Imagin, which Shin-chan mispronounces as "Himajin", including calling Momotaros a red Buriburizaemon, who Momotaros identifies (and summons) as the legendary Imagin. When Ryotaro transforms into Kamen Rider Den-O Sword Form so they can defeat the evil Imagin that has appeared, Shin-chan jumps up and manages to transform with him into Kamen Rider Shin-O. When the door opens on Misae, she is insulted by Momotaros just as the Fatass Imagin attacks the group. Den-O takes a beating until Shin-O glues the Fatass Imagin's three fat asses together, leading the Imagin to want to go back in time to erase any day Shin-chan was on time, only to find none exist.
Den-O destroys the Fatass Imagin, saving Shin-chan and Misae who leave just in time to find that the bus has left without them. The Owner, impressed by how Shin-chan has helped them protect the flow of time, allows Misae and Shin-chan to go back in time to just before the bus arrived. Bidding farewell to their new friends, Shin-chan realizes he still has to use the toilet, but while fighting with Misae to get to the toilet, soils himself just as the bus rolls up.
- Ryotaro Nogami/Kamen Rider Den-O (野上 良太郎／仮面ライダー電王, Nogami Ryōtarō/Kamen Raidā Den'ō ?) - A very unlucky young man who discovered the Rider Pass, and eventually uses to become Den-O to fight the Imagin and protect time/space.
- Hana (ハナ, Hana ?): Another sigularity point like Ryotaro, Hana helps in protecting time/space while keeping Momotaros in line.
- Naomi (ナオミ, Naomi ?): Den-Liner's caretaker/maid who is extremely hyper and does not get surprised easily, sticking to her belief of making only coffee despite her batch being poorly made to non-Imagin.
- Owner (オーナー, Ōnā ?): The strange man who owns Den-Liner and has a habit of speaking in complexes when it comes to the nature of time.
- Shinnosuke Nohara/Kamen Rider Shin-O (野原しんのすけ／仮面ライダーしん王, Nohara Shin'nosuke/Kamen Raidā Shin'ō ?): A kindergarten-aged boy whose antics are the basis for his series, prefers to be called Shin-Chan. While going to the bathroom one morning before school, Shin-chan is transported aboard the Den-Liner. There, he causes mischief for the crew and passengers. He becomes Kamen Rider Shin-O to help Den-O fight an Imagin that has contracted itself with his mother.
- Misae Nohara (野原みさえ, Nohara Misae ?): Shin-chan's mother, a homemaker of age 29 and is angered easily whenever Shin-chan makes fun of her or mocks her by acting like her, with the standard retaliation physical: spanking, screwing fists, pulling cheeks, and even striking his head to produce enormous, but temporary, lumps. But her intent for Shin-chan to get to school on time inadvertently had her open a contract with an Imagin, endangering herself and the Den-Liner crew.
- Momotaros (モモタロス Momotarosu?): The hot-headed Imagin that first possesses Ryotaro, aiding him in Sword Form to fight other Imagin rather than fulfill his contract. He is also the subject of most abuse from Hana. Momotaros plays a part in summoning Buriburizaemon into the present by removing his shoulder pads and clapping them together like two coconuts.
- Three-Leveled Ass Imagin (三段腹イマジン Sandanbara Imajin?): An Imagin that forms a contract with Misae Nohara while she's trying to get Shin-chan out of the bathroom so she can get him to the bus on time.
- The Legendary Imagin (伝説のイマジン Densetsu no Imajin?): This Imagin is depicted as Buriburizaemon (ぶりぶりざえもん Buriburizaemon?), an anthropomorphic pig who appears in Shin-chan when ancient Japan is discussed, a quite cowardly/lazy/treacherous/funny sort who talks like a hero. Momotaros identifies him as the Legendary Imagin. Once summoned by Momotaros, Buriburizaemon gets himself contracted to Shin. He has a habit of disappearing while attempting to speak.
- Ryotaro Nogami/ Den-O Plat Form (野上 良太郎／電王プラットフォーム, Nogami Ryōtarō/Den'ō Puratto Fōmu ?) - Takeru Satoh (佐藤 健, Satō Takeru ?)
- Shinnosuke Nohara (野原しんのすけ, Nohara Shin'nosuke ?) - Akiko Yajima (矢島 晶子, Yajima Akiko ?)
- Hana (ハナ, Hana ?) - Yuriko Shiratori (白鳥 百合子, Shiratori Yuriko ?)
- Naomi (ナオミ, Naomi ?) - Rina Akiyama (秋山 莉奈, Akiyama Rina ?)
- Owner (オーナー, Ōnā ?) - Kenjirō Ishimaru (石丸 謙二郎, Ishimaru Kenjirō ?)
- Momotaros (モモタロス, Momotarosu ?) - Toshihiko Seki (関 俊彦, Seki Toshihiko ?)
- Buriburizaemon (ぶりぶりざえもん, Buriburizaemon ?) - Kaneto Shiozawa (塩沢 兼人, Shiozawa Kaneto ?, Archive Voice)
- Misae Nohara (野原みさえ, Nohara Misae ?) - Miki Narahashi (ならはし みき, Narahashi Miki ?)