Here are reliable places in Romania to buy comfortable cotton pajamas (online + in-store), with short notes and sources:

• eMAG — huge selection of cotton pajamas (many listings labeled 100% cotton). (emag.ro).
• Fashion Days — multi‑brand fashion marketplace with many cotton pajama sets (women’s, men’s, kids). (fashiondays.ro).
• ABOUT YOU / Zalando / Answear — fashion marketplaces that stock cotton sleepwear from brands like WE Fashion, Skiny, Tommy Hilfiger. (aboutyou.ro).
• LC Waikiki — wide, affordable range of 100% cotton pajamas in stores and online across Romania. (lcwaikiki.fr).
• Pepco — budget-friendly, seasonal cotton pajama sets (physical stores nationwide). (pepco.ro).
• Specialist sleepwear/lingerie shops (Intimissimi/Intisimo, Astratex, Evanoir, Pijami.ro, PijamaleRomanesti.ro) — good for higher‑quality or specifically‑cotton pieces. (intisimo.ro).
• Trendyol and other marketplaces — lots of cotton sets at various price levels and fast delivery options. (trendyol.com).

Quick buying tips

• Look for “100% cotton”, “combed cotton”, “cotton jersey” or “cotton flannel” in the product composition for softness and breathability. (tresstextile.com).
• Check size guides and return policies (especially when buying online). Fashion marketplaces and large retailers normally offer easy returns. (fashiondays.ro).
• If you sleep hot, choose lightweight cotton jersey or cotton‑modal blends; for cold months choose cotton flannel. (tresstextile.com).

If you want, tell me a city or price range and I can find specific listings or the nearest physical stores and current options.