Isekai Konyoku Monogatari

"How am I supposed to fight with this?!" After being summoned into another dimension as one of the five heroes destined to defeat a demon lord, Touya Houjou awakens his hero power only to discover that... it's an unlimited bath? He was blessed with the power to create a bath that can be accessed anywhere, which seems to spell doom for his quest to defeat the demon lord. As he recovers from his shock, Touya slowly discovers the unique features of his power, which allow him to use it in ways he'd never dreamed of... But will he ever get any bath time with Haruno Shinonome, the beautiful girl who was also summoned along with him?!

(Source: J-Novel Club)