I have a feeling there's no great/easy solution for this. My coworker bought me a kindle book for Christmas

. I don't have a kindle, and I don't want to read it on the kindle app on my phone. I also don't want to bug him - so I accepted the gift. And now I'd like to read this book on my kobo.
My wife has an old kindle she doesn't use (she currently uses kobo, too). Can/should I register that device with my amazon account, so I can download the content (as far as I can tell I can't download it to my computer without having the correct registered device)? And then I'd need to strip the DRM in order to put it on my Kobo?
Any other solutions? I just want to read this book! It was a good gift.