In both books, the protagonist is (or at least appears to be) suffering from schizophrenia (or some analogous condition); in both books, the attainment of mature adulthood is accompanied by the abandonment of role-playing games.
ɪn bˈoʊθ bˈʊks, ðə pɹˈoʊɾɐɡənˌɪst ɪz ɔːɹ æt lˈiːst ɐpˈɪɹz təbi sˈʌfɚɹɪŋ fɹʌm skˌɪtsəfɹˈɛniə ɔːɹ sˌʌm ɐnˈæləɡəs kəndˈɪʃən; ɪn bˈoʊθ bˈʊks, ðɪ ɐtˈeɪnmənt ʌv mətʃˈʊɹ ɐdˈʌlthʊd ɪz ɐkˈʌmpənid baɪ ðɪ ɐbˈændənmənt ʌv ɹˈoʊlplˈeɪɪŋ ɡˈeɪmz.