Given the following context:

Sylvester (who lives in an apartment building next to Tweety's yard) hears Tweety Bird singing and looks through the window with his telescope. Tweety sees him, grabs a towel, exclaims "I taw I taw a peeking tom cat!", and shuts the door after saying "That nasty old peeking tom cat!".
Sylvester sees Hector the Bulldog (called Spike in this film) sleeping next to the pole that holds Tweety's birdhouse. He sneaks and climbs the pole. Spike awakens and pulls him down. Sylvester smiles and pushes Spike's straight face into a happy face, but Spike changes his face to furious and chases him back to his apartment.
Sylvester uses a grabber to grab Tweety. Tweety avoids it until Spike climbs up a ladder and uses the grabber to knock Sylvester repeatedly against the wall, while Tweety scolds Sylvester saying, "Bad Old Puddy Tat!".
Sylvester builds a robot dog, but it attacks him, so he destroys it with a baseball bat.
Sylvester makes a smoke bomb and dashes into the smoke-covered yard, bumping into Spike, who then pounds him before sending him out of the yard.
Sylvester uses a pogo stick to approach Tweety's birdhouse, passing Spike and grabs Tweety. As he is about to pogo away, Spike opens a manhole. Sylvester falls in and he nicely makes Tweety escape but, Spike drops the lid with 4 holes on Sylvester's head.
Sylvester makes a storm cloud formula to prevent Spike from coming, but he trips, creating a storm in his room instead.
Sylvester makes himself invisible using vanishing cream, hits Spike with a brick and grabs Tweety. As Sylvester climbs down the pole, Tweety wonders why he is floating. Spike sprays Sylvester with green paint, forces him to give him Tweety and punches the cat out of the yard.
In a final attempt to get ride of Spike, Sylvester makes a bomb camera, but Sylvester trips down the stairs causing it to explode. Sylvester appears with angel wings, saying "Hmph! It's a good thing pussycats have got 9 lives".

answer the following question:

What is the name of the character who sneaks and climbs a pole? 

Sylvester