In such cases, the fourth frame has something to appeal to people's emotions, such as touching scenes, or to drop a hint of something to come in the next piece and to give the readership expectations; thus, although it is not something to draw a laugh, it is appropriate as an 'ending of a story.'
この場合の4コマ目は、感動させるなど情動に訴えるものや、次回への伏線を貼って期待を持たせるものなど、“笑いどころではないが「話の結末」としては適切なもの”になることが多い。