Because of her poor health, Hotaru can actually be taken by force fairly easily, but she doesn't mind being tied so long as she's asked in advance. For her sake that's often the better option anyway. Both her civilian and senshi forms nicely emphasize her legs so her outfit choice often falls to personal preference based on whether or not she's wearing pantyhose at the time. It's best to stick with simple gags for her as well as she needs to be able to breathe well just in case she has one of her attacks. So long as she's treated with care, she won't put up much of a fight and will appreciate the attention.