", ▁a ▁Sk ov ox ▁Bl itzer ▁is ▁drawn ▁to ▁the ▁school ▁by ▁the ▁Doctor , ▁who ▁is ▁pos ing ▁as ▁Co al ▁Hill ' s ▁care t aker . ▁He ▁cl ash es ▁with ▁D anny , ▁mock ing ▁his ▁past ▁in ▁the ▁Army ▁and ▁ref using ▁to ▁accept ▁that ▁he ▁is ▁a ▁Math s ▁teacher , ▁bel ieving ▁he ▁is ▁more ▁su ited ▁to ▁the ▁role ▁of ▁a ▁P . E . ▁teacher ▁( to ▁the ▁point ▁of ▁nick nam ing ▁him ▁" P . E ." ). ▁Clara ▁strugg les ▁to ▁balance ▁her ▁life ▁with ▁the ▁Doctor ▁and ▁her ▁relationship ▁with ▁D anny , ▁especially ▁as ▁neither ▁one ▁knows ▁about ▁the ▁other . ▁ ▁However , ▁when ▁D anny ▁becomes ▁susp icious ▁of ▁the ▁Doctor ' s ▁activities , ▁he ▁disco vers ▁the ▁truth ▁about ▁Clara ' s ▁time - tra v elling ▁activities . ▁Although ▁he ▁initially ▁strugg les ▁to ▁come ▁to ▁terms ▁with ▁the ▁idea , ▁he ▁gives ▁Clara ▁his ▁bless ing ▁to ▁continue ▁trav elling , ▁but ▁war ns ▁her ▁that ▁there ▁may ▁come ▁a ▁time ▁when ▁the ▁Doctor ▁push es ▁her ▁too ▁far , ▁remember ing ▁similar ▁individuals ▁from ▁his ▁time ▁in ▁the ▁army . ▁ ▁D anny ▁makes ▁brief ▁appearances ▁in ▁subsequent ▁episodes ▁in ▁the ▁series , ▁and ▁he ▁supports ▁Clara ▁when ▁she ▁dec ides ▁to ▁stop ▁trav elling ▁with ▁the ▁Doctor ▁after ▁he ▁puts ▁her ▁in ▁a ▁vulner able ▁position ▁in ▁" K ill ▁the ▁Moon ". ▁However , ▁Clara ▁is ▁unable ▁to ▁resist