noun
possessiveness; desire to monopolize; desire for control
A strong desire to have someone or something all to oneself, often with a negative connotation of jealousy or unwillingness to share.
彼の独占欲が強すぎて、友達と遊ぶのも許してくれない。
His possessiveness is so strong that he won't even let me hang out with friends.
独
Out of a desire for control, she secretly checked his phone.