喰らいつく literally means “to bite into” or “sink one’s teeth into,” but it can also mean clinging desperately and refusing to let go. In this song, it describes relentlessly fighting for the future one wishes for, giving the word a fierce, animal-like sense of determination. Its unusual kanji and powerful metaphor make it especially memorable.
"怪物" means "monster", and the song is told by someone who can smell their own wildness. YOASOBI wrote it as the opening for the anime Beastars, and you can hear the predator in it right away: "クラクラするほどの良い匂いが" (a smell so good it makes me dizzy) hits "ツンと刺した鼻の奥" (stinging deep in my nose), and the singer wakes up "目を覚ます本能のまま" (following the instinct that wakes up). Then comes the creepiest line in the song, "今日は誰の番だ?" (whose turn is it today?). It sounds like a hunter picking a victim. The opening toast, "あぁ 素晴らしき世界に今日も乾杯" (ah, cheers again today to this wonderful world), is sarcastic, because the next lines call the city's laughter "作りもんさ" (just something fake).
The fight in the song is against that instinct. "喰らいつく" (to bite into, to sink your teeth in) is a word for animals eating, and the singer uses it for grabbing hold of the future they want. Near the end it turns into "弱い自分を何度でもずっと / 喰らい尽くす" (I'll devour my weak self, again and again), which is a great twist: the monster eats its own weakness instead of someone else. The middle section is a pile of questions about how to live, like "ありのまま生きることが正義か" (is living as I am the right thing?) and "本当の僕は何者なんだ" (who is the real me?). Learners should notice "僕" (a casual "I", usually used by boys and young men) all through it. The answer the song lands on is simple and a little sweet: "ただ君を守るそのために" (just so I can protect you), the singer runs to "僕の中の僕を超える" (surpass the me inside me).