If you want a summary about their relationship:
Wild Tiger (Kotetsu) is the unpopular veteran hero who got paired with a young and promising young hero called Bunny (Barnaby), both has their share of bickering and oftentimes acts like an old couple, and Bunny has a tendency to bridal carry Tiger if he falls during their mission together. Their relationship can be called cute, since both Tiger and Bunny actually tries to understand one another during the course of the story.
As for Samurai Flamenco, it's an anime about a model who secretly works as a vigilante hero called Samurai Flamenco during the night who got his identity accidentally discovered by a policeman during his mission. The policeman always take care of Samurai Flamenco during the course of the story, and just can't leave him alone (he often stays and watch movies together with the model). The model-slash-hero actually struggles with his feelings towards the police.
Both shows have BL undertone to it and equally enjoyable to watch (Also, if you like One Punch Man you will definitely like both series), but I think Samurai Flamenco are faaar more shippable. But each to their own....
Does the tiger and bunny anime have a subtle bl text to it? A sho ai ship?