world ▁with ▁H ades , ▁where ▁he ▁becomes ▁pale ▁and ▁sh ag gy - ha ired ▁and ▁begins ▁we aring ▁dark ▁cl othing . ▁N ico , ▁despite ▁being ▁very ▁powerful , ▁is ▁extremely ▁lon ely , ▁much ▁like ▁his ▁father . ▁He ▁makes ▁nearby ▁people ▁un com fort able , ▁partially ▁due ▁to ▁his ▁un ner ving ▁weapon ▁of ▁choice : ▁a ▁sword ▁made ▁of ▁iron ▁co o led ▁in ▁the ▁St y x ▁(" St yg ian ▁iron "), ▁capable ▁of ▁absor bing ▁mon sters ' ▁ess ences ▁rather ▁than ▁ban ishing ▁them ▁to ▁T art arus . ▁Until ▁meeting ▁Cup id ▁in ▁The ▁House ▁of ▁H ades , ▁N ico ▁also ▁strugg les ▁hiding ▁his ▁hom osex ual ity . ▁During ▁The ▁Blood ▁of ▁Olymp us , ▁N ico , ▁Re yna ▁and ▁H edge ▁transport ▁the ▁Ath ena ▁Par then os ▁to ▁Camp ▁Half - B lo od . ▁Between ▁The ▁Blood ▁of ▁Olymp us ▁and ▁The ▁H idden ▁Oracle , ▁he ▁begins ▁a ▁relationship ▁with ▁Will ▁Sol ace , ▁a ▁child ▁of ▁Apol lo , ▁after ▁adm itting ▁to ▁Per cy ▁that ▁he ▁had ▁a ▁cr ush ▁on ▁him . ▁ ▁N ico ' s ▁suggestion ▁that ▁Per cy ▁takes ▁on ▁the ▁cur se ▁of ▁Ach illes ▁and ▁his ▁work ▁to ▁conv ince ▁H ades ▁to ▁fight ▁in ▁The ▁Last ▁Olymp ian ▁is ▁cru cial ▁to ▁the ▁Olymp ians ' ▁success ▁and ▁ear n ▁him ▁a ▁short ▁bout ▁of ▁fame . ▁He ▁is ▁priv y ▁to ▁the ▁fact