This is our very last piece!
—Aikurō Mikisugi remarks before releasing the S.S. Naked Sun

S.S. Naked Sun (裸の太陽丸 Hadaka no Taiyōmaru?), also known as the Naked Sol, is a thin bodied and wide topped carrier constructed with funding from the Takarada Conglomerate and is Nudist Beach's last line of defense; the organization released her as a way to rescue Lady Satsuki from Honnōji Academy, dubbed "Operation Rescue Satsuki."

The S.S. Naked Sun is dry docked in the underground Nudist Beach base under Osaka. During launch, the Dōtonbori gate will open and Osaka will begin to part itself as the ship is lifted through the water to her floating position.

She is powered by several turbines resembling oversized Hamster wheels, with the crew being the hamsters. When run by Mako Mankanshoku wearing her 2-Star Goku Uniform, it was able to withstand the ridiculous amount of speed it was gathering.

In her closed form, she resembles a seam ripper, an item used for removing threads from clothing. Incidentally, Aikurō Mikisugi dubs it as the Great Naked Dagger and uses the aforementioned boost to help Ryūko Matoi destroy the Original Life Fiber, speeding right through it and blowing a hole on its back, leaving the Naked Sun's lower deck stuck on one of Honnōji Academy's walls, while the Blades fell into the City. Before the final assault on Honnōji Academy, the cast had Mitsuzō Soroi's tea and then ran into the entrance to the Academy.

The S.S. Naked Sun is seen again in episode 25 as it's still stuck on the lower deck of Honnōji Academy's walls. It was wielded as a weapon by the Honnōji Academy's "Final Defense Apparatus", activated by Rei Hōōmaru to take vengeance on the perpetrators of Ragyō Kiryūin and Nui Harime's death, but was quickly destroyed by the Rending Scissors' Final Graduation Mode.