Why do people feel the liberty to ask personal questions about my sexual life when I "come out" or let them know my sexual orientation?

People are generally inquisitive, they're just most likely intrigued, however you shouldn't feel pressured to answer any questions you don't feel comfortable asking.

The nice answer is to say, "They are just curious" but my honest answer is that it's pretty rude, it is an example of entitlement and a show that they are uneducated and have decided to put it on you to educate them. Furthermore it is a way of highlighting that they perceive you as "other". You don't have to tell anyone anything you don't want to and it's ok to reinforce your if this makes you uncomfortable, it is understandable! If you have the patience to educate them, that's ok too. :)

It often seems rude for the person to do this, but if they don't have a common sexual orientation, people get curious and want to know more from a real-life person.

People are curious and may be attempting to understand you by asking these questions. Answer only the ones you feel comfortable answering and don't forget to remind them that being LGBTQ is not all about sex and shouldn't be discussed only in those terms. It's about affection, love, and companionship - just like heterosexual relationships are.

Individuals are curious and many times don't seem to think through what exactly it is they are asking. If someone asks you a question about your sexuality you don't have to answer them. They may want to learn about different genders and orientations, but you aren't obligated to be the one to teach them.

Because people are curious about things they didnt experienced by themself, therefore they try to get to know something about it from people who are "into this"

Most persons just want to know what the life of a gay/bi or tans is most are curious and may have a liking towards it or just want to have a knowledge

Some people just don't understand how personal it is, and they think that just because you told them about your orientation you're ok with telling them anything. Someone, because of prejudice, believes that people of certain orientation are overly focused on sex and so more ready to talk about it. When it happens, you can just tell them it's something personal, and you simply told them about your orientation because you wanted them to know that part of you, but your sexual life is yours alone.

I hear what you are saying, I am not sure why people feel that they can ask what they want just because you have disclosed to them your sexual orientation? I am wondering how it is that you respond when these questions are asked

I think that people are curious because either they don't understand and would like to or they are questioning their own sexual orientation. I find it helpful to create and maintain healthy boundaries in a situation such as this. For example, if someone asks me a question I am uncomfortable answering, I might say something like this... "Dear Person, I understand that you are curious about my sexual orientation. However, I do not feel comfortable sharing with you detailed information about my sexual life."