Before concluding the question in the title, do you feel being vulnerable is a weakness or strength? Because your answer and perception are quite important for you, to open up in the aspect of sex. Mostly, the word vulnerability is considered as a weakness or a bad term that is used for low self-esteem and emotional strength, but indeed this is a term that must be used positively, especially when it comes to intimacy in a relationship. If having sex is the ultimate form of showing love, then being vulnerable is the ultimate form of showing yourself the way you are in a romantic relationship.
Forget about the economic and social vulnerabilities in a person, for a top-notch intimacy in a romantic relationship; a person must confront one's physical and emotional vulnerabilities. We may have sex with various people with various emotions and feelings. We sleep with hookers for having sensual fun and fulfilling sexual fantasies, we sleep with random people we meet on virtual and real spaces to get rid of stress or to explore one's self or orientation, but we sleep with our loved ones to express our intense emotions in every possible way. Of course, you can be that person who sleeps with any kind of person to express the love and lust, there's no wrong in it. Do you know, the vulnerability in a person differentiates the sensual experience of one's various sexual encounters?
Stop considering vulnerability as the possibility of being attacked or harmed and start viewing it as the possibility of knowing and opening up to others, especially to your partners. Well, you don't have to be vulnerable to every person. That may sometimes make you end up with unpredictable consequences. But you must be vulnerable with your romantic or sexual partners. If you have a random hookup with a random stranger, you don't have to explain yourself or opening up to the person completely, in your first meet. But if the same person becomes your romantic partner by forming an emotional attachment, you need to be vulnerable and open up about yourself more than ever, to strengthen your bond.
You don't become weak if you express your feelings, emotions, preferences, likes, dislikes, tastes, and your complete self. Instead, you become much stronger than before and more comfortable than ever. And you can't open up just like that to any person, including your partner. It requires trust, passion, feeling, and emotion of love and most importantly, the physical and emotional intimacy.
Yes, sex creates an emotional and physical vulnerability in a person. It is the only channel that makes a person open up better. It works in different ways for different people. If you think that genital penetration, can make two people feel vulnerable to each other, then you are wrong. Sometimes, all you need is an emotional intimacy to be vulnerable to your partner.
Sex is the only act that makes two naked bodies meet and get inside of each other to explore the sensuality of a relationship. If you are okay with seeing a person naked in front of you, why aren't you okay with expressing your emotions to the same person? Are you scared of whether your partner may judge you? Are you afraid that your emotions can be taken for granted? Or are you ashamed of being yourself and expressing emotions just to prove that you are a typical strong personality who doesn't express emotions but handle them alone? Whatever you are and whatever you feel, sex creates the vulnerability in you and it will surely make you open up with someone. It isn't necessary that it could be your partner. Many men don't open up to their partners, but they completely express all their emotions to random people they hook up with. Because sometimes, sex creates that comfortable atmosphere where a person strips off his/her emotions and come clean with his/her feelings to his/her partner or partners.
Vulnerability is not about expressing your details, your financial expenses, or anything related to materialistic issues. The physical vulnerability makes a person express how he feels when he gets touched, how she feels when she gets caressed, how he feel uncomfortable in a particular sensual act, how she feels the pain during intense penetrations, how he likes to be enticed, how she likes to be cuddled, how he enjoys a particular sensual act, how she wants her body to get embraced or treated, etc. If you don't express your feelings regarding how you must be treated in bed, then how come your partner comes to know during sex? Until and unless you feel physically vulnerable and express all your likes and dislikes in bed, your sexual or romantic partner can never understand and there are chances that you may end up feeling bad about the sex and your physical attachments.
The emotional vulnerability can be created between two people who have an emotional bond of good at emotional intimacy. Being vulnerable with a person is a big thing, but you need to express your emotions by opening up yourself with your romantic partner to have a proper connection. Firstly, you need to be willing to express your emotions. Say what you want and what you like. Give compliments and tell how getting compliments from your partner make you feel. Express what you think instead of faking for the sake of sex. If you are having sex with your partner, the most important thing is you need to experience pleasure by being with him/her. You won't be portrayed as weak at all if you express these little emotions. People like their partners to be emotionally vulnerable to them because that makes a person feel connected and loved.
You may think that you don't have to be vulnerable, but sex has the power of unleashing the vulnerability in a person. So, sex surely creates a vulnerability, but you need to be willing to make yourself vulnerable to your romantic partners. And if you don't want to be vulnerable, wait for the day till your sexual encounters become emotional burst outs. Simple!