Onaga 

A character from the Mortal Kombat series. He has the appearance of a humanoid dragon. He is the former ruler of Outworld and the predecessor of Shao Khan. He is a boss character and one of the most powerful characters in the Mortal Kombat universe. Often referred to as "The Dragon King Onaga".

Onaga is a big scary dragon boy huh?

Onaga by Gir-Geed July 1, 2023

Frye Onaga 

Hailing from the Onaga Clan, Frye is one of the two lead singers in the fictional Idol group "Deep Cut". She is also the better singer as she doesn't sound like she's holding back tears like Shiver Hohojiro. In Splatoon 3's story mode, she is seen to play a Pungi flute and wear a wooden eel mask.

"Frye Onaga's forehead is a normal size, her hairstyle (tentaclestyle?) just accidentally highlights it."

Frye Onaga by AerosprayMG>RG January 5, 2024

yoroshiku onegai shimasu 

Basically, this is said as an entry-level phrase to someone you have a favorable impression with, or if you are a very 'traditional' person. Another situation you would use this, is if you were being convinced to accept someone's hospitality. I am unfamiliar with the direct transliteration, but if you wash the grammar properly it comes out to be 'Please treat me kindly' or 'Please take care of me' or 'I am in your care, kindly' something to that effect. As you can see, this phrase is a trade of trust, where you 'ask' for trust, and 'give' trust by 'placing' yourself in someone's care.

Source? My frequent visits to Japan, and familiarity with its culture.

'Yoroshiku onegai shimasu, senpai.'

- Here, an underclassman at school or work who might have previously met this person they refer to as 'senpai' (or senior, upperclassman) Implores them to continue their goodwill now, and in the future. The meeting may be in front of the senior's friends, so the person wants to be respectful so their senior doesn't lose face.

yoroshiku onegai shimasu by Taketo November 26, 2013

Onagad 

When a guy drinks too much but can still get hard enough to have sex. However, you are so drunk that you can't get off by having sex, so instead you jerk yourself off onto the girl.

Man can you believe Mike Onagad it again last night?

Onagad by Machoman Randy Savage April 7, 2008

Ongatronious 

What you say when you want to sound smart but you’re actually stupid.

Crikey mate! That elbow is ongatronious!

Ongatronious by B.P. Savage1327 February 21, 2019

onegai 

the japanese for please

onegai teacher or onegai twins

onegai by steven jones March 30, 2005

oniga'd 

When someone blurts an uncontrollable spazz at something that shouldn't be spazzed at.

Joe: Yo, out of my way.
John: Shut the fuck up eat a dick, fucker!
James: Wow, you just got oniga'd.

oniga'd by Liam Makes Words. October 9, 2008