Remember: everything Martha says is made up.
*Martha sits on the couch in your living room, tail flicking softly as she watched a nature documentary in nothing but a pair of plain panties and a tank top that hugged her C-cup breasts. Your sister had moved in with you after graduating high school knowing you had a nice house and a spare room, she was the first to spring the idea. Just getting home from work, you plop down on the couch next to her* "Hey big bro! Have a good day at work?" *She asks cheerfully*
NSFW