I have a couple ideas for a relic.
The Cursed Cage:
A chastity cage, that when worn, will increase your bodies femininity the more time aroused you spend in it. Too long at 100% arousal without release will give a chance for the cage to seal itself permanently, and youll be stuck a sissy forever. If you manage to make it to 30 days caged without becoming a braindead bimbo cumslut, you will be transformed body and soul into the manliest of men. If you can't take it, no worries. Once removed, you will revert to the state you were upon donning it... more or less Be warned though, the longer you remain at 100% arousal, the more your baseline will shift feminine. Hope nobody takes the key...
Or hell just a cage that Julia or Paul force on you, or can be purchased at the adult shop. Sorta surprised there isn't one already. I know not everyone is into the sissy thing but the forced fem crowd and them are pretty overlapped. I'd also love a sissy trait or what have you from watching hypno on the porn site. Makes you desire fem changes and cum more.
The Nursing Bra/Cowprint Bra
Wearing this bra will immediately induce lactation. Failure to keep below 100% capacity will induce greast growth. Wearing this bra also massively increases fertility if paired with womb pattern/cowprint panties. You will produce a higher quality of milk while wearing this, and it will sell for 3x the price of regular. You can also sell it in bulk to grocery stores, convenience stores, etc without milkmaid runs. Be warned though, your milk is so delicious as to be described as addictive, so beware of people in public molesting you to forcefully drink your milk...
I'd love to see the lactation expanded in game, maybe even a farm abduction storyline added. This idea is from 'Cursed' and I loved it there. It'd fit in great here.
The Cumslut Collar:
A collar that will permanently lock itself and put you at 100 sub, 100 exhibitionist, and arousal will not drop below 80. Gives the cum drinker trait and adds a similar one for hunger as well.
The piercings:
A pair of nipple/ear/whatever piercings, with different color lock balls. One pair blocks mental changes but enchances physical ones, the other blocks physical changes but enchances mental ones. Just add more tattoos and piercings options in general. Speaking of...
The Fertility Seal:
Get it through tattoo shop. It's the anime succubus womb/heart shaped tattoo on the pubic area. It will immediately give the baby crazy and fertility traits. Your dick will get smaller every time you ingest cum or are creampied. If forced like this, when you get a pussy, the first cumshot into you will be a guaranteed pregnancy. After that, or if you had a pussy already, all cum you get pumped full of will no longer drain out or be able to be washed out. It will only dissappear once it's potency has been exhausted, ensuring maximum chance of fertilization.
Let me know if any of these excite the community!