Accidentally killing someone still makes them dead. Unintentionally raping someone still makes them raped. Rape is what happens when not everyone involved in the sex act wanted it to happen. If you accidentally violate someone, that doesn't make it a non-traumatic event and it doesn't make it the victim's fault or 'responsibility.' If you violate someone sexually, you are 100% responsible for that happening.
If people have a hard time saying no to you, that's on you. Make it easy to say no to sex and easy to say no to particular sex acts. It's not a grey area. If you can't trust someone to say no to you when they don't want to have sex, DO NOT HAVE SEX WITH THEM. If you don't know their signals and/or triggers, 1) ask what they are and 2) check in regularly during sex.
Guess what? consensual sex is more difficult than rape. It takes more work. It takes more attention. It takes more communication. If you haven't bothered to do the work on learning to pay attention, ask questions, & check in, and you sexually violate someone without intending to do so, that's not a 'misunderstanding' -- it's the most common kind of rape. Most rape is not done with malicious intent, but rather through selfish indifference.
Also, if you make it easy to say no, you will have less sex. This is a thing. You're gonna have to be okay with that if you really want to make sure that you never pressure anyone into sex they do not want and thus violate them sexually. Someone who might have had sex with you had you just started feeling them up without asking may choose not to when you give them a conscious choice by asking, because that brings in factors besides "does this feel good?" So what is more important to you, knowing that the person considered all factors and chose to have sex with you, or getting to interact with them sexually by skipping the conscious choice option? If you don't want to risk them having gone along with it against their true wishes, then you have to find out their true wishes by fucking ASKING.
I never touch someone sexually or in any way that attempts to arouse them without a verbal confirmation that yes, they want that. And frankly if you're not willing to ask first every time, then you don't EVER get to play the 'misunderstanding' or 'accident' card.
Even the most careful person can still make someone feel sexually violated if there has been previous trauma. I have experienced that with a partner who was careful about consent; they immediately noticed when something was 'off' in my expressions/reactions and they stopped, asked what I needed and gave that to me. I have been on the other side too, when I bumped into a trigger that my partner did not know they had -- I was paying attention to their reactions and noticed, stopped, asked what they needed, and gave it to them. I don't think sex with a consent-careful partner ever has to progress to the point of damage; it may be impossible to always avoid negative things coming up, but it is completely possible to keep from adding additional trauma.
Further discussion of this kind of rape: the 'feigning ignorance' consent violation tactic: if they care, they change their behavior. TW: rape