俺氏 is read as おれし (oreshi) and means I.
おれし
oreshi
おれ
I
どうし
same surname
かれし
boyfriend
りょうし
both persons
し
clan
せし
Celsius
げんじ
Genji (the character in the Genji Monogatari)
せっし
げっし
Yuezhi (ancient Central Asian people)
うじ
かし
Fahrenheit
へいし
Heike family