Lois Lane and Superman kissing

Krypto mentions being kicked out of Superman's bed when Lois "stays over". Superman and Lois are dating at this time.

Krypto mentions that he was just hit by a car. Another character remarks, "You never forget your first time." With an obvious sexual double entendre.

Guinea pig says Lex Luther is "hot"

There is a passionate kiss at the beginning of the movie by Louis and Superman.

A young dog grabs ahold of a toddler by the arm to save her. Red bite marks are shown.

A lot of comic book style action, with characters being knocked to the ground, held down, and manipulated, often by psychic powers.

The protagonist pets are threatened in an extended scene with a cat that shoot missiles from its whiskers, a machine gun in its tail, and vomiting grenades. Lots of explosions take place.

Once the (apparent) f-word is "bleeped" in the film. Then two uses of the apparent "S" word is bleeped out. There are a couple of minor euphemisms.

Guinea pig says "Unhand me you wench" to the pet rescue worker

A villain kitten with superpowers coughs up a grenade, pulls the pin out and says "See you in heck" before throwing it at the super hero pets.

There are several times animals begin to talk negatively and the scene cuts from English to animal noises. Some are implied to be cussing others out.

"Suck," "crap," and bleeped (albeit clear) uses of both the f-word and s-word as mentioned above.