If you're into the mix of ecchi, action, and supernatural elements that 'Highschool DxD' delivers, there's a whole world of anime that scratches the same itch. For starters, 'Testament of Sister New Devil' is practically a spiritual sibling—supernatural battles, cheeky fan service, and a protagonist caught in a wild power struggle. Then there's 'Trinity Seven', which blends magic school shenanigans with a harem dynamic and a protagonist who’s unapologetically bold. 'Campione!' also fits the bill, with myth-based action and a dash of romance.
For something slightly different but still in the same vein, 'Shinmai Maou no Testament' pushes boundaries even further with its themes, while 'Masou Gakuen HxH' leans into mecha and ecchi. If you’re after more comedy, 'To Love-Ru' is a classic, though it’s lighter on the action. Honestly, the fun part is discovering which of these clicks with you—some lean harder into the fan service, others into the lore, but they all share that addictive blend of chaos and charm.