Alvaro is getting his butt poked.

Álvaro's ass hurts, as it does every day when he leaves his Master/Tutor/Trainer's house. The injections he gets in his butt cheeks are painful, often making him cry as the liquid enters, but he knows it's part of his training and it actually turns him on more each time, because besides reminding him of the session, it makes him think about the next one, about fulfilling his duties and coming back on his designated day and time, even though he knows his butt will be pricked a couple more times, like every day he visits the Tutor. The beginning is almost always the same. Upon entering, he receives a couple of slaps, undresses to his underwear, kneels before the Master, kisses his feet, and thanks him for allowing him to submit again. The Tutor, who sometimes puts a dog collar and leash on him and walks him on all fours to the room, or sometimes makes him stand up, gives him a good kiss and simply tells him to come in, not even bothering to ask. Álvaro already knows the first thing is the injection, although he doesn't know if it will be just one and the second one will be given just before he leaves, or if they will be both together, or when he will have to present his butt for the second one, but what is certain is that he will receive at least one prick right away, before moving on to anything else. Some days the Tutor tells him to lie down and prepare his butt while he prepares the injection, other days he has to be licking his feet in the meantime, others he has to lick his balls or suck him off, it varies, but the butt pain is always the same after the cotton with alcohol, the little slaps to relax, the quick and dry prick and that liquid that sometimes enters slower and sometimes faster, but always hurting a lot and causing moans or tears that Álvaro, at 20 years old, can't avoid... The Tutor, who is so serious and strict about it, is then quite understanding and affectionate when he cries... he kisses him, caresses him, and comforts him, although he always reminds him that he will give him all the necessary injections because he needs them to be well trained. It was easier to get used to licking the Tutor from head to toe, including balls and armpits, sometimes sweaty, sometimes clean. And not so easy, but still pleasurable, opening his ass more and more with the help of lubricants, the tongue and fingers of the Tutor, who often make him moan with pleasure... Now he can take being fucked with the harness and the 20 cm cock/dildo that the Tutor wears, hard and thick, and that the Tutor likes to thrust deep and use to penetrate him for long periods with strong thrusts reminding him of how much of a slut he is and how he likes being fucked in the ass/pussy... He knows there is still much more to learn...he often hears words like electro, rain, wax and others from the Tutor as he speaks of all the things he still needs to discover, and he knows that little by little he will overcome and get used to not only the injections, which he finds more and more enticing even though they hurt, but also to new things that will bring him new pleasures...