Riku, a popular driver for Sakegawa Deliveries, can't stand Yuichi, a rival delivery driver. Yuichi's unfriendly, he's cocky, and worst of all, is incredibly strong for being so shrimpy! Then one day, he gets a package addressed to Yuichi... Knowing the package contains sex toys, he impulsively tells Yuichi to use the toys in front of him. The next thing Riku knows, he's rock-hard! Can he turn down Yuichi's erotic advances when he asks for something harder than his vibrator!?

(Source: Renta!)

Note: Includes an extra chapter.