This is definitely something you shouldn't be dealing with right now. If it isn't consensual, say "no". If he doesn't stop, tell your parents or call the police if it gets to that point.

What is consensual?

Yes this is abuse and needs to be stopped. If you can't prevent him from doing this to uou then you need to tell someone who can stop him. If you are still young and living with your parents please tell them asap.

Consensual means that both of you agree to what is happening. It means you say to him "its ok that you are doing this to me". But it is not consensual because you dont want this done to you and its right that you dont want it done to you.

Please tell someone its happening or fight back. Push him away and scream or lock your door if possible. If you dont have a lock wedge a chair under the doorknob so he cant get in. But ultimately it would be best if you told someone you trust what he is doing to you.

Since he is your brother, it's still considered sexual abuse, or incest.
Even if you both 'wanted' and said it was ok, doesn't make it right.
Most victims who have been abused for a long while, sometimes (sibling or not) will say yes or even seek out the abuse (attention).. they know something isn't right, but the feelings around it feels good...

With me, I wanted to make everyone happy... even at my own cost.. so I learned that bad attention ( being beat up, or kicked, or even sexual stuff) made 'them' happy, so I 'let' them beat me up...
I didn't like it, but by 'letting' them do it to me, at least they paid attention to me...

To answer your question, yes, he is sexually abusing you.. even him asking you to take your clothes off is a form of sexual abuse..

If you want it to stop, tell an adult, and don't let adults tell you to let it go, or stop talking about it.. it won't stop then..

Hang in there,
Keep talking in here.. write in your journal..

We are here to listen to you and all on here!

Notalone!

I agree with the above consensus. Please find someone to help you. We will try to be here for you as much as we can.

I know it may be hard, but do your best to get some help. I went through something similar and waited 15 years to say something and I wish I would have gotten help earlier. You don't deserve this and know you're not alone. Do the best you can and reach out to any trusted adult- a teacher, parent, counselor, coach. Anyone. You owe it to yourself to say something. Hang in there and take care of yourself.