Time for a Sexy Party! event is a limited time event (until Monday (it has been extended to Wednesday), 22nd September, 3 PM PDT 2014) which includes new Costume for Stewie Griffin, decorations and buildings.
Event description :
After reading Plaything Magazine, Stewie really wants to throw a sexy party! Make his dream come true by crafting his Sexy Stewie Outfit! Limited time only!
New Costumes : Edit
-Sexy Stewie for Stewie.
New Buildings :
New Decorations :
-Lawn Tiger (for those who missed it in previous event)
If you complete the questline you also get Sexy Stewie Robe Station as reward.