Similar to my recent upload of Swimsuit Conversions for these ages, I present to you, Briefs!
The Sims 4: All Outfits In The Simtimates Kit
The Inside Scoop on The Sims 4 Teen Pregnancy Mod! — SNOOTYSIMS
The Sims Resource - Seams Pants
The Ultimate List of Aesthetic Sims 4 Teen CC for High School Gameplay - Must Have Mods
Mod The Sims - Basic Male Briefs Pack - five styles for Teen, YA and A
busra-tr BEARS SET-352 (TOP) BD978 Sims 4 custom content, Sims 4 mods clothes, Sims 4
The Sims 4 is getting DLC undies and messy bathrooms in two new kits
Play With Ageing With These Age Up and Down Cheats! — SNOOTYSIMS
The Sims Resource - busra-tr