The "How a Girl's Body Works" series explores the shy, intimate mechanisms of a girl's body. This time, petite and adorable Momoko Arimura appears. Measurement begins with her soft, quivering lips. Her tongue measures 5cm—thick and slightly long—indicating Momoko is skilled at blowjobs. Next is measuring her areolas. As results are recorded in a sketchbook, her nipples react instantly to touch, highly sensitive when pinched. Her round, plump breasts exude erotic charm, with a cup size between C and D. Moving on to erogenous zones, measurement starts from the clitoris. Her clean pink pussy and erect clitoris are carefully measured—Momoko smiles from pleasure with just light touches, and the sight of slippery juices dripping from her slit is a major highlight. On all fours, she spreads her buttocks for anal examination. When stimulated with a vibrator, her untrained, tight anus twitches visibly. Vaginal temperature is recorded at 35°C—slightly low. Temperature changes after sex are also monitored. Finally, experience creampie sex with Momoko. After ejaculation, a thermometer is inserted into her semen-filled pussy for a follow-up temperature check.