Can't sit or stay for this warm-hearted rom-com? You must be a cat person.

Your patience with “Dog Days” may be directly proportional to one simple fact.

Are you a dog person?

Check that box and you’ll put up with plenty, from a bloated running time to predictable story arcs. There’s an undeniable sweetness to the film all the same along with some hidden strengths.

Take the sneaky smart comic asides from a talented cast. And don’t discount a whiff of romance you know is coming but feel all the same.

Add one stone-cold fact of life. Dogs never blow a reaction shot.

Ever.

The story follows several characters who all share a love for our four-legged friends. Vanessa Hudgens is Tara, a kind-hearted coffee slinger smitten with the local vet. Elizabeth (Nina Dobrev) hosts a chirpy L.A. morning show and is struggling to get over her cheating beau.

Ron Cephas Jones of “This Is Us” fame plays a widower whose dog runs off when he suffers a medical scare.

Think they’ll end up in the same frame by the finale? That doesn’t require a crystal ball of any kind.

The film’s finest players get a variety of screen time. Thomas Lennon crushes his scant scenes as a beta male Dad in distress. Tone Bell gets far more to do as Elizabeth’s potential squeeze. Someone give him a rom-com, stat. He’s a first rate charmer with potent comic chops.

The big surprise? Adam Pally as the prototypical slacker. The sketch comedy alum knows when to sell a line and when to barely utter them. The latter elicits the bigger laughs.

FAST FACT: According to PetFinder.com, dogs experience dreams in a very similar way to how humans do.

These “Dog Days” characters flirt and fumble, careening from one pat scenario to the next. There’s nothing offensive here beyond a dog sticking his snout in a diaper pail. This is pure PG-rated storytelling, and its heart is aggressively in the right place.

The best story arc belongs to Hudgens and “Baywatch” survivor Jon Bass. You know where their connection will go by the third act, but the journey is finely calibrated. Bass’ puppy eyes never waver. It’s Hudgens who shines as a woman slowly realizing her friend’s inner strength.

“Dog Days” serves up a third act that simply will … not … end. We crave sappy resolutions in movies like this. Must the screenplay dot every single “I?”

It can’t help itself, and it’s hard to get too grumpy about it. After all, there’s always room for another cute doggie shot, even if Cesar Millan might cry Uncle before the credits roll.

HiT or Miss: “Dog Days” is cute and cloying, sweet and predictable. Your mileage may vary based on your affection for our canine friends.