It is weird how scent works, isn't it? If a loved one passes, every once in awhile you'll notice a small that just reminds you of them. When going through their left belongings, walking by someone with a particular perfume, etc. When my better half was taken young by cancer, I noticed that his lingering smell in his pillows, our blankets, etc was even comforting and calming. It's neat to see Zack and Elize reacting to each other on even such a primal base -- a scent base -- and knowing it is also totally human.