sneak
e.g.
A year later... right before the ceremony, I tried to quietly sneak the cub out and return him to the mountains. The adults were outraged with me. 一年経った頃… 儀礼の前に私が黙って小熊を山に逃がそうとしたからみんなに凄く怒られた (
/yupeco/『ゴールデンカムイ』
12話)