This is a very tricky matter for a man to get right. Generally speaking this is the reserve of only the closest of couples. Certainly not territory for new relationships. Don’t forget that a woman is always making decisions about you, based around your underwear choices, so when you hand the choice to her, it can be a bad sign. However it doesn’t always work out badly. In some very rare moments “his & hers” underwear can be very successful. Simplicity is key. You should not be agreeing to matching red , lacy thongs! It’s recommended that it is saved for intimate moments and not a regular ritual – perhaps deployed when one of you are travelling, as a means to keep you close.