וְאַ֨ךְ אֶת־דִּמְכֶ֤ם לְנַפְשֹֽׁתֵיכֶם֙ אֶדְרֹ֔שׁ מִיַּ֥ד כָּל־חַיָּ֖ה אֶדְרְשֶׁ֑נּוּ וּמִיַּ֣ד הָֽאָדָ֗ם מִיַּד֙ אִ֣ישׁ אָחִ֔יו אֶדְרֹ֖שׁ אֶת־נֶ֥פֶשׁ הָֽאָדָֽם׃
내가 반드시 너희 피 곧 너희 생명의 피를 찾으리니 짐승이면 그 짐승에게서, 사람이나 사람의 형제면 그에게서 그의 생명을 찾으리라
Rashi
ואך את דמכם HOWEVER YOUR BLOOD — Although I have permitted you to take the life of cattle yet your blood I will surely require from him amongst you who sheds his own blood (see Bava Kamma 91b).
Bekhor Shor
But (ach) your blood of your lives will I require: Because it permitted to spill the blood of beasts, it forbade the spilling of the blood of man, even one's own blood. [This is] so that they will not say, "Is it not that [since] the blood of a beast is permitted for us to spill because they live through us, [so] too a man who lives through himself should be permitted to kill himself? Hence it is stated, "of your lives I will require"...
Chizkuni
ואך את דמכם, “yet your (human) blood”, etc; this is a warning to any animal not to kill any human being, as G-d would hold it responsible for harming humans. Rashi explains the verse as follows: the peculiar wording is to include killing, including suicide that does not involve the actual shedding of blood, such as by strangulation.