Tina loves to swallow obese prey or prey with a certain proportion of their body larger than normal, because she can have fun playing with her meal which is stuck in her stomach, which is visible from the outside of her stomach, and do whatever she wants with her meal, before she digesting it. It's like the prey is stuck in organic bondage and Tina is the dominatrix.
(P.S. it's not Lydia, to reassure people, just another cow with breasts as big as Lydia.)