Not necessarily, although it is recommended to boil/submerge your cup/disc in freshly-boiled water during the beginning and end of your monthly cycle.

Yes. R/evolution has provided different ways you can sanitize your cup/disc like using your R/evolution sterilizing cup. For more information, you may visit [Menstrual Cups] [Menstrual Discs].

R/evolution menstrual cups/discs are in the darker side of the color spectrum for a reason. They are less prone to staining and discoloration. However, if they still become stained and if you want to remove these stains, submerging your cup/disc in vinegar may work, just make sure that you remove all traces of vinegar afterwards and before further use. However, remember that staining is normal due to constant contact with blood but it does not mean that the cup/disc is unsafe to use so we don't recommend trying to remove the stains anymore.

There is little to no chance of leaking during the short moment that you have to throw out the contents of your cup/disc and rinse it out, unless you have a drastically heavy flow and/or there is a lot of menstrual blood left on your vaginal wall. If blood has grazed your vulva while removing your cup/disc, it may appear as a leak--you can always just wash/wipe this down, though.

If a sink is in your bathroom stall, you may dump out the content of your cup/disc as you normally would at home. However, if you have no access to a sink (or if it is outside your bathroom stall) your sterilizing cup will come in handy as you can fetch water from the sink and use it to rinse out your cup/disc while in the bathroom stall after dumping the contents in the toilet bowl.