My wife really wanted a pen holder that looked like a stack of books and I was unable to find one. I tried my hand at modifying an already made model as I have zero skills in modeling at this time. I took the book and stacked them offset a few times, and then cut a hole in the “middle”. I do realize there are one or two spots where it's not sealed fully, but the location didn't bother me enough to try and fix it. If you're bothered by it you could add a simple shape in your slicer to cover them up, but again you'll likely never see them. 

Overall, for my first ever custom print I was really happy with how this turned out, and so was my wife which was what mattered most. I figured there may be one other person out there who'd like something like this so why not share it with all. Feel free to remix, edit, do whatever to this as I am very new at this and did such a quick and dirty model that I'm sure it can be improved. Thanks and enjoy!