4:15 I think Bakugo cried during his second fight with Deku, when Bakugo was expressing his feelings of guilt for having ended All Might career since he believed it was his fault.
The aforementioned Bakugo suffered a heart rupture as a side effect of his personality awakening. The basis is from the single book No. 37 1. Nitroglycerin is originally a drug that can dilate blood vessels during heart attacks. 2. Personality awakening leads to excessive secretion of nitroglycerin 3. In addition to being released from sweat glands throughout the body, it also affects the heart. 4. Acute vasodilation > drug-induced hypotension > reflex ventricular pulsation ＞Rapid rise in blood pressure＞Myocardial infarction＞Heart rupture 5. Because in this perspective view, Bakugo is shown from the side with his back inverted and facing to the right. So the heart you see here is looking through the left armpit into the chest. That is, the right side of the picture = front view, and you can see the open wound on the left side of the heart. It means that the wound is located on the left side of the heart 6. The left atrium and ventricle are originally the places where blood pressure is first received when blood returns. So it happens to be the most common damage location when myocardial infarction is complicated by ventricular rupture. You can go back and look at the heart part. There is an obvious crack on the right side of the heart.
Bakugou sweats a nitroglycerin-LIKE substance, it's not actually nitroglycerin. Whatever it is, it's volatile and prone the igniting/exploding like NG. I personally think the blunt force trauma from SFO's attack not only crushed his chest/possibly heart but it also caused the substance that was circulating through his heart to explode. In the manga you can see the pressure lines going from his chest to his back from the hit, but there are also pressure lines from the front wall of his heart in the opposite direction, leading outwards.
Not very important but to answer at your question "did we see Bakugou cry before?" yes, he did but only to express his feeling to Deku (first after Deku vs Kacchan 1 when Deku ran after after him and in DvK2 when he crying his guilt that he was the cause of All Might end)
Ich habe so sehr geweint als ich die Episode gesehen habe und damals das Mangakapitel! Ich war also drauf vorbereitet und dennoch hat es mich hart erwischt. Und um eure Frage zu beantworten. Ja, man hat ihn schon mehrfach Weinen gesehen. Einmal als er mit Deku in Staffel 1 gekämpft hat, in seinen Kampf mit Deku gegen All Might und später als er sagte "Warum war ich derjenige wegen dem All Mights Karriere zuende ging", er hat da sicherlich nicht extrem geweint, aber geweint
