She and Kimihito love them! And that's not the only addition in mind!

"...so, how do they feel?" Kimihito asked Cerea, who blushed as they looked at her breasts. She flushed, and cupped them.

"They feel so... Unchaste..." she murmured. "But... I do enjoy them... Though I hope that they don't leak..."

"They won't~!" Miia chirped. "I also made it so that they only release the milk when the nipples are being suckled! Don't want to end up crying over literal spilled milk, after all! Too wasteful and messy! Oh, and I also made the milk nice and sweet~!" she added, gushing over her perfect creation.

Cerea flushed deeper, but started to undo her blouse, removing it, and letting her Master and sister servant see her slightly grown melons. "...do thee wish to suckle them?" she asked shyly, turning her head and covering her mouth with a fist.

Kimihito didn't need telling twice, and leaned in to suck on her engorged nipple. He felt her warm milk flow into his mouth as she gasped, her head jolting up, and she bit her lip, quivering. "...you made it feel good for her to get sucked too?" he asked Miia, pulling back and swallowing the mouthful he had gotten.

"Indeed I did, Master," she crooned. "She'll make a fine addition to the harem~! Honestly, I don't think we even need to put any kind of magical obedience compulsion on her to spice things up, she's already obedient! Not like it's strong enough to **** her anyway, unless you want it to be! I could just give her the part where her pleasure centers are rewarded with each command though!"

"Do it..." Cerea moaned as Kimihito fondled her other boob, and he nodded, and made the wish. Once Miia granted it, he sucked out enough to ensure she wouldn't get lopsided. Cerea crooned as she felt the spell take hold, then yelped as Kimihito, feeling bold, cupped her face, and kissed her. Her eyes widened as she felt and tasted her own milk flowing into her mouth. Her eyes softened, and she surrendered to her lust, returning the kiss and swallowing the milk.