My advice to you is give the book a try and see if you like it. You say you dont like that book now but maybe once you are into it you will like it. But if you truely dont want to read it and want to give it back, tell your friend the honest truth. Dont lie about reading it because…
1) your friend might ask you questions about it and you wont answer them right and she or he will figure out you lied about reading it.
2) lies always find there way back to be reveled
And 3) you dont want to lie and ruin your friendship.
Hope this works,