I recently found this sentence in Kiki’s Delivery Service, as spoken by Jiji, her male cat.
「どうして、コキリさんに秘密にするのさ」ジジは、めんどうくさそうにいいました。「だってさ、かあさんはひとり立ちのことになると、大げさにさわぐんですもの。」
The さ’s threw me for a loop, so I’m wondering if anyone could help figure out their meaning?
The closest I’ve found is that it’s a manly version of saying ね as a sentence ender, but that doesn’t seem to make much sense for the だってさ segment, さ?
Also, might be interesting to add to the pool of grammar for bunpro?
It’s there!
I’m so confused, I kept trying to search it in the search function. Thanks!
This is a nice showcase of it being used if you don’t mind vtuber stuff
My favorite explanation of さ compared it to saying “like” in English, which I do all the time. 
it can absolutely be a filler word like “like.” i honestly hear it the most with little kids that are taking faster than they can string the words together lol
A lot of young people use さ a lot. My wife’s sister often times, particularly when she’s speaking super fast/worked up/excited/etc she will go
私さ、昨日さ、職場さ、ステーキ食べてたさー
And at first it basically meant that I couldn’t understand anything she was saying because the use of さ completely took me out of comprehending mode. But now my brain knows when to just basically discard that sound. Its kinda like when people go ya’know as a filler. Sometimes people use it WAY to much and you’re like STOP SAYING YA KNOW so much.