On her face.

Kenji fell back against the wall with a roar. His cock popped out of Shoko's mouth a moment before the first rope of semen splashed on her mouth and nose. Caught off guard, three more jets of cum splattered her face before she could finally react and stick his cock back into her mouth. She moaned as she struggled to guzzle the stream of semen that seemed endless.

"Gah!" Kenji gasped, thrusting his hip forward to release the last spurt of cum into the doctor's throat. Shoko stroked his shaft and squeezed his balls, trying to milk more jizz from him. When she was satisfied that he could give no more she popped his cock head from her lips, licked it clean, and gave it a playful kiss.

"Very impressive, Mr. Kataoka," the young doctor smiled at the still rock-hard erection in her hand. "Now we know you can ejaculate, at least with fellatio. So we can rule out the physical cause of obstruction ejaculatory ducts."

Kenji nodded weakly, still recovering from his first blowjob.

"That said, we still need to know if you can ejaculate from other methods of stimulation," Shoko stated matter-of-factly while she scooped the sticky white cream from her face and licked it off of her fingers as if it was icing on cake.

"What do you mean other methods, Dr. Sugimoto?" he asked with curiosity.

Shoko smiled at his perked interest.