SL-man is a sentient steam locomotive in the "Sore Ike! Anpanman" universe, designed for rail transportation, goods delivery, and transporting children. His physical design echoes classic steam engines like Thomas the Tank Engine, featuring "SL" on his cab to denote "steam locomotive".

First appearing in Episode 62a, SL-man was discovered rusted and immobilized after a lightning strike. Baikinman kidnapped him, misjudging him as non-sentient. Revived by fruit from Dokinchan, SL-man sought to repay Baikinman, who manipulated him into believing Anpanman was an enemy. Tricked into attempting to push Anpanman’s bakery off a cliff, SL-man was intercepted by Anpanman, who exposed Baikinman’s deceit. This revelation led SL-man to ally with Anpanman and thwart the villain.

He shares a significant bond with Poppo-chan, identified as his only child. Their relationship, central to his character, began in Episode 1089a.

SL-man’s abilities include emitting an SOS signal via his smokestack during emergencies and generating black smoke to distract foes like Baikinman. He traverses both rails and off-road terrain, with his arms moving during locomotion.

In real-world settings, life-sized SL-man replicas serve as ride attractions at Anpanman Children’s Museums in Kobe and Osaka. He also appears as playground equipment at the Takashi Yanase Memorial Hall. SL-man and Poppo-chan remain the sole sentient trains depicted in the series.