Wildcats are a food item, and there's an option to kill one in an encounter, as well as several cat NPCs you can fight. If you count lions, plenty of those suffer and die.
No, but the retired July storyline had a father attempting to convince (possibly coerce) his daughter to let him impregnate her. She refuses, but he repeats that he has the intention of breeding with her. The same character also coerces his wife into performing rituals with him that appear to have a sexual component. Also, during the February event, it's possible to watch animals mate without their knowledge, and one encounter shows consensual sex between a dwarf lion and a lioness; the player has the option to intervene in a way that the lioness clearly did not expect.
A former storyline revolved around a young adult being abused emotionally and sexually by her father. The event has since been retired, but you can still find details on the wiki.
Lots and lots of sexual jokes, especially during the February event, as well as animals mating on screen. Think the PG-13 version of National Geographic, with more anthropomorphism.
They're lions, so they're always naked. The were-lioness in the October event is bipedal/humanoid and she does have visible nipples, but I don't know if she would count.
One of the February encounters has a maneless lioness which your lion can make fun of. Maneless lions in your pride have their own favour text which includes your lion mistaking them for a lioness.
Tricky; the flavor text and narration do sometimes mention lionesses being attractive and in a sense, the lionesses are treated as objects or 'prizes'.
Yes, the flavor text for leopons and tigons often mentions infidelity. Otherwise, as in nature, it's a mechanic of the game that you can mate with multiple lions in your pride.
During the retired July event, a father attempts to impregnate his daughter. She refuses and gets away unscathed, but he repeatedly states his intentions to breed with her. Also, as the player, it's possible to mate with your own children, siblings, and mother.
The lions hunt, and all artwork of food items is fairly realistic. Many events have death in their plots and in encounters. If you're upset by animals dying, this probably is not the game for you.