Yes, it's called autoeroticism, or more commonly known as self masturbation.

Which is when one stimulates them self sexually.

It is perfectly normal, healthy, and safe.

Yes, a person can engage in homo-sexual activities with themselves, known as autoeroticism or self-stimulation. This can involve masturbation or other forms of self-pleasure.

The term "autoeroticism" refers to behaviors designed to obtain sexual satisfactionwithout the intervention of another person (the most obvious example being masturbation-1). However, the term is often understood more broadly, given the Freudian conception of psycho-sexuality, according to which many different physical pleasures take on the value of sexual satisfaction. Genitals are not necessarily involved. By extension, the same can be said of certain psychic activities (reading, according to popular wisdom, is a "solitary vice"). "Alloeroticism," a less common term, refers by contrast to sexual satisfaction obtained with the help of another person.

I'm hoping you are referring to 'autoeroticism,' and that the question rightly asks, "What is the effect of autoeroticism on male bodies?" I spite of centuries of disparagement, the practice of masturbation remains a normal and naturally self discovered method of sexual learning and appreciation. If all of the studies of the supposed harm resulting from the habit were piled up, no one person could read them in a lifetime. Yet the self amusement and enjoyment continues unabated. Physicians tried to quell the practise in the mid 1860s by introducing circumcision to the USA. Although that surgery on 2-4 day old males has been proven to dampen the sexual enjoyment of masturbation, it certainly did not slow the number of pubescent teen males satisfying themselves in this manner. No proven disadvantages have ever been ascribed to masturbation. It remains a safe, enjoyable method of self introduction to the world of sexual adventure.

Children at the two-year-old developmental stage, are all about impulse. Normally, goal of disciplinary measures is to teach a child that there are consequences to their actions. Because they don't process cause-and-effect the way an adult does, discipline to a child at this stage, regardless of chronological age, means something entirely different. Discipline at this stage should be more about redirection. Changing their focus is often all that is needed. If the child is capable of learning, they will eventually get the message that doing whatever it is they were doing, is not appropriate. Children may get frustrated and act out when you attempt to shift them from one thing to another, so read up on strategies to handle these outbursts. Puberty brings about not only physical changes, but emotional changes as well. You may find the child needs more sleep than they used to, and may be more emotionally labile. This will especially be true because non-verbal children are frequently frustrated from being unable to express the confusing feelings he or she is going through during this turbulent phase of a child's life. A peri-pubertal child at this developmental stage, may have difficulty processing normal societal inhibitions when it comes to masturbation and expressions of his or her sexuality. As such, you may need to pre-plan your responses to things like inappropriate erections or displays of autoeroticism in public. You will need to be alert for things that may trigger such a response in the child, so you can avoid them. Be aware too, that children reaching sexual maturity in advance of their mental development, are at much greater risk for exploitation. There are many resources for parents of developmentally disabled children, but you have to be your child's best advocate because the system is designed to help the maximum number of people for the minimum cost. There are support groups popping up on the Internet all the time, a simple search will yield many positive results. Be strong and vigilant, and bless you for taking on such a vital and difficult role.