They gradually improve

The tourists attack their assigned tasks with renewed gusto. Although the caning wasn't directly related to their attempts to satisfy you, it appears to have helped them focus on overcoming their understandable resistance to what is being demanded of them. The tongue at your arse squirms energetically, if not particularly skilfully, the muffled sound of retching a pleasing counterpoint to the wet slobbering as Yuina makes another determined attempt to swallow your dick. After a word of advice from you, she immediately begins clumsily licking your frenulum and sucking on your shaft at the same time.

Her eyes watering, the attractive Asian finds an angle where she can use her bodyweight to put extra pressure on the back of her throat, stoically ignoring the constant gagging this causes. From the way her hands twitch, you surmise she'd like to use them to shove your manhood down her gullet, but is justifiably concerned by your reaction. Despite her efforts and the help of you pushing down on her head, she's still stuck, so you switch to only using one hand and pick up the cane with the other to give her a quick flick on the backside.

It's more shocking than painful, but something shifts and suddenly her throat is distending to accept your girth, intensifying her body's involuntary attempt to expel the invader. Nevertheless, she fights through and forces herself down, inch by inch. You have to remind her again of the importance of tongue and lips, but eventually her nose reaches your belly in a passable first crack at a blow job. While she struggles against the urge to vomit, you turn your attention to her girlfriend, giving her advice on improving her technique. You're not sure how much she understands, but by the time her mistress is on the verge of suffocation, she's making love to your bum hole with passion and tenderness.

You let the elder girl up for air, whereupon she gulps in much-needed oxygen. You decide you can let her practise some more later and switch to her arse for now. It's no looser than her neck and you revel in the sight of her face screwed up in anguish when you use your thumb to press the tip of your prick inside. She wiggles in an effort to take you deeper, so you give the usual advice, but she's still so tight that it takes a few moments and more than a few tears before she's bouncing agonizingly (for her) on your phallus. The stimulation is very pleasant, but you've not forgotten your intention to concentrate on teaching the girls oral techniques, so you pull out and order Himari to take her turn sucking you.

She shows much less discomfort swallowing the cock that's just been up her lover's bum than licking your own crack, so you repeat the previous exercises, going from her (tight but accommodating) arse to Yuina's throat. Again, the dominant half of the couple has difficulty with the oral skills, but she's already showing definite improvement.

The constant changing of positions serves another purpose, helping you keep control so that you can prolong the experience, because although the young couple lacks the exquisite skill of the students you enjoy on a daily basis, the encounter is pleasurable enough that you could easily climax at any moment.