The Treatments airborne, she's already been breathing it in from Diana's stench

"it's in the air you're breathing right now, it's all the lovely stench that my wonder ass has been putting out" Diana laughed out as a squelchy bout of gas exploded out of her rear for effect, Selina recoiled in horror as she realized whatever the treatment would do to her, it was too late to escape, she'd most likely already been infected, before she could even finish her train of panicked thought her stomach roared in discomfort at her as she was overwhelmed by hunger pangs.

"ahh!! so...so..hungry!!" She cried out, buckling over onto her knees, squelching into the mess around her as she put her hand out to grab Diana's vast stomach for support, her hand slipped on the grease and mess covering the amazons' belly and fell face first into the mulch, quickly rising back up gasping for air she felt her hunger renew with each breath, she didn't care about the now filthy state she was in, she just needed to fill her stomach.

"Oh Selina, you're so funny when your hungry" Diana giggled, as she pressed another button off to her side, from the same hatch that her own feeding tube was dangling a secondary tube snaked its way down, resting on Diana's corpulant belly as it coiled up, "Go on hun, dig in" Diana smirked as she returned to her own feeding.

Selina couldn't bare the hunger any longer, she cast aside any worries she might of had and grabbed the tube from Diana's belly and jammed it in her mouth as she began to suck at the sludge that was now pumping its way down the pipe into her waiting gullet. the taste impacted her mouth in a euphoric wave, she once more reached out to steady herself on Diana's belly, not losing her grip this time as her stomach cried out in ecstasy at the sensation of being filled by the food paste.

Her senses drowned in a sea of gluttony as time began to lose meaning for the rapidly fattening cat burglar, Wonder woman just looked on in content amusement as she resumed her feeding and just pumped more and more gas out of her ass