ore-sama 俺様

In Japanese, ore-sama 俺様 is the over-the-top combination of the first person pronoun, ore 俺, and the reverent honorific suffix sama 様. Basically, ore-sama means the same thing as ore, "I," "me," in English, except it's ridiculously pompous and people would only use it in real life as a joke.

Which means it's mostly a trope used in manga and anime. (just like kisama 貴様.)

Manga: School Rumble, スクールランブル (Chapter 66, The Razor's Edge)

• ore-sama ni
  fukujuu se yo.
  俺様に服従せよ。
  Submit to me.
  • I command thee to submit to THE GREAT ME.
• e...
  え…
  Eh...

Characters use ore-sama to imply they're extremely important. It's used by the type of character that would say "I'm the strongest" or "the smartest" or "the bestest" or stuff like that.

Manga: Zatch Bell!, Konjiki no Gash!! 金色のガッシュ!! (Chapter 1, 清麿、正義の味方)

• yakamashii'!!!
  やかましいっ！！！
  [You're] noisy!!!
  [Stop annoying me!!!]
• ore-sama ga, nande
  anna tei-reberu na
  yatsura to tomodachi ni
  nan'nakya
  ikeneendayo'!!?
  オレ様が、なんであんな低レベルな奴らと友達になんなきゃいけねーんだよっ！！？
  Why do I have to become friends with low-level guys like those!!?
  • tomodachi ni naru
    友だちになる
    To become friends.

That doesn't mean it's true, though, it just means that's what they think about themselves.

Manga: Dragon Ball, ドラゴンボール (Chapter 225, ナッパ ても足も出ず)

• ko' kono ore-sama ga
  taishita koto
  nai dato......!!!!
  こっ　このオレさまがたいしたことないだと･･････！！！！
  Th-- this me isn't [a big deal], [you] say......!!!!
• sou da
  そうだ
  [That's right.]
• ima no kougeki de
  wakatta
  いまの攻撃で　わかった
  With [that] attack [just] now [I] realized.
  (Goku figured Nappa isn't a big deal from how weak his attack was.)