Clearly, those anti-fart underwear filter manufacturers need to hire a better advertising department.
Hell, you can get them via subscription on amazon prime.
A lot of them work on similar technology to masks, too.
This is actually real.
Name: "Subtle Butt Disposable Gas Neutralizers"
$13 (for 5)
Amazon Link:
https://www.amazon.com/dp/B001KYVJSC
There weren't any videos really showing what it did besides these infomercial-like clips, which is weird since you'd think Buzzfeed would do some "We wore fart pads for a week" type thing.
Reviews are all really good. It's funny, a lot of them come from people who bought it as a gag gift but bought more for themselves later.
Subtle Butt: disposable gas neutralizers (5 saving graces) https://www.amazon.com/dp/B001KYVJSC/ref=cm_sw_r_cp_api_glt_fabc_u1YcGbJ4W1C3Z?_encoding=UTF8&psc=1
Fart filter:
Febreze isn't discrete, but it is designed to neutralize odor. There are also these: https://www.amazon.ca/Fashion-First-Aid-Disposable-Neutralizers/dp/B001KYVJSC
Obviously, diet is king, though. There are many foods that cause smellier gas.
Here's the link to the Amazon page: Subtle Butt: disposable gas neutralizers (5 saving graces) https://www.amazon.com/dp/B001KYVJSC/ref=cm_sw_r_cp_apa_KhyLBb0PVVG98
These might help.
Maybe your partner could try wearing these in his underwear:
Apparently these are real, Amazon has them for sale