"夢遊せんせい" is a Japanese phrase that means "dream travel teacher." It is not a common term and is not typically used in everyday language. However, it could be used in a creative or metaphorical context to describe someone who guides others through their dreams or who helps them explore the realm of dreams.
In English, the phrase "dream travel teacher" is more commonly used in the context of lucid dreaming, where an individual learns to become aware that they are dreaming and can control their actions within the dream. A lucid dreaming teacher might teach techniques to induce lucid dreams, help students remember their dreams, and guide them in exploring and manipulating their dream worlds.
If you're looking for a more standard Japanese term for someone who teaches about dreams or dream interpretation, you might use "夢の解析やり方を教える先生" (yume no kaiseki yarigata wo oshieru sensei), which means "a teacher who teaches how to interpret dreams."