It sounds much more suitable as a child's bedroom and bath than the master suite. I was going to say it would work until I came to the part about it being a long narrow space with the windows only at each end. Any chance of adding more windows?

Carolyn,
I haven't explored pricing, but I'd love to put in a couple gables or skylights if gables are cost prohibitive.

Do you have angle walls? If yes, can you tell us how much space you have to stand up easily?

Suzanne,
The walls angle in at 4.5 ft up. They angle in about 2.5 ft. and the ceiling is 7'9" high.

Here are the dimensions:

There's certainly enough space there for a bedroom, bath and closet, even with the sloping walls and low ceiling. A skylight would work nicely in the bathroom and a dormer or two added to the bedroom would make a very pleasant room.

Thanks, Carolyn! Any suggestions on the placement of the bedroom, bath and closet? The front of the house faces west. I'd prefer to keep dormers/skylights on the back of the house, the east facing side. How many square feet would you recommend for a proper bathroom? I was hoping to fit a glass shower, toilet, and vanity at the least.

Is the window on the south end centered on the wall? Where is the window on the north wall?

Suzanne,
The window on the south end is centered (pic on left.) The one on the north end is centered as well but the stairs come up from the second floor at that end (pic on right.) Sorry about the mess. The room is my kids' playroom aka dumping ground right now.

Carolyn,
Thank you so much! That looks awesome! Your input is MUCH appreciated!

You are very welcome, shakersables. That shower I drew is 60 x 48", big enough for any shower lover. You could certainly add a door to the walk-in closet, something I failed to do.

The center of the vanity would be dropped in height to allow for the window. The "closet cabinet" opposite the bed would be equipped with doors on the front and you could place a TV above it, either wall mounted on the sloping wall or on top of the "closet cabinet". The cabinet would have a rod for hanging things and space below for shoes.

Carolyn,
It looks and sounds amazing! This will be quite an upgrade for us. It's very exciting to imagine the possibilities! Thanks for your help!

Very well thought plan Carolyn. I like the symmetry of walls and doors position. It is not only practical but also pleasing to the eye.

Thank you, Suzanne! It was fun to draw it. I'm usually just doing furniture drawings.

Looks great, Mandy!

I hope you'll let us know how things are progressing along the way, Mandy.

Carolyn, I definitely will! We just finished our kitchen remodel so it may be a while.

Carolyn, not only you did a fantastic job on the walls and doors position on Mandy's master ensuite, I had noticed that you did very well in the placement of furniture as well. I am participating in another discussion asking for a layout of furniture, would you like to join and give your comments on what I have suggested. Maybe you can do better:
https://www.houzz.com/discussions/furniture-layout-dsvw-vd~496781

Thank you, Suzanne, for the kind words. I much appreciate it. I took a look at your furniture layout dilemma you were working on and posted a drawing. You really made it easy for me by figuring out all the room dimensions! Thanks for inviting me into that discussion which I had missed. Carolyn