Peke changing herself into Lala's signature outfit.
Dressform is a Deviluke program installed into Peke that allows her to transform into all kinds of outfits.
Outfits
Dressdorm can create every outfit any character has ever needed, and presumably can be used for literally any outfit. With it, Peke has changed into school uniforms, gym uniforms, alien uniforms, swimsuits, bikinis, dresses, lingerie, etc. It's also allowed Peke to change into what usually isn't considered to be clothing material as long as it helps make up the outfit, such as frosting.
Yui's outfit change after being hit by one of Rito's Dressform projectiles.
Only seen when Rito took over Peke's body and lost control, Dressform can also be used to throw projectiles that change the outfit of whoever they come into contact with. The outfits that the projectiles create seem to be mostly random, but at least somewhat influenced by who sends them (i.e., Rito was highly aroused at the time he threw his projectiles, so those who were hit by the projectiles were given revealing new outfits).